For your first miniatures they look really good. I don't see any spots where you painted over the shapes and you also have some nice darklinings already and some basic highlights.
My personal advice wold be to stick to a classic layer method with relativly opaque layers before trying advanced techniques. With classic layering I mean paint all areas with a respective base color. Then mix a brighter and a darker tone and paint highlights and shadows over the base color. The more colors you mix, the "smoother" transitions you get.
That way you learn to:
1. Mix colors
2. get a feeling how colors behave, flow, cover etc.
2. Brush control
3. understanding the basic concept of light and shadow
Especially brush control is important at the beginning since you train your muscles to do all these small controled movements and to hold the mini steady without shaking to much. There aren't that much tips or tutorials around that since you kinda need to find a pose that is comfortable for you to hold your mini and brush.
Wet Palette and thinning:
Most painters (me too) use a wet palette. It keeps your paints from drying for quite some time and also feeds them some water. You can find a lot of tutorials on youtube on how to build and use one. You can also buy wet palettes. I use the wet palette from RedGrass Games and I'm very happy with it. But I used a self made palette for years, just got too lazy to cut baking paper into sheets for my palette. The bought one also got the benefit (although I don't really know how they do it) that it doesn't mold when you leave the palette with the lid closed for a couple of weeks.
Thinning:
The first "tip" beginners get is probably to thin their paints and paint multiple thin layers. This is a kinda double edged sword in my opinion. A lot of beginners (me included back in the days) tend to overdo the thinning. Especially when you use a wet palette it can become to thin since the paint also pulls water from the palette. Thin the paint enough so it flows well off the brush but not so much that it floods the surface you want to paint for your base color. Thinning ratios make little sence since every paint is different even if it's the same paint range and it also depends on the humidity in your room, the temperature what palette you use and so on. You will get a feeling for that over time.
So my advice concerning thinning would be to thin it a bit to make the paint flow well but don't thin it to much so that it doesn't really cover anymore. Coverage also depends on the tone you use of course.
Washing/Drybrushing/contrast paints
There are a lot of so called beginner techniques and products out there but I personal am not a big fan of those. It depends on what you want though. Contrast paints are rather new and I only tried em once but washes and drybrushing have been around for ages.
If you want to paint an army with lots of models for playing then this is probably the way to go. It's fast and you can achieve good results for the table. But it has it's limitations. Especially drybrushing is not a very controlled technique and often leads to somewhat dusty look. Washes also can be hard to control. They bild pools if you aply too much and can leave "coffee stains" after drying.
There are people though that achieve really great results with washing techniques (often then using washes from oil colors) in combination with airbrush and glazes. But to achieve that it takes a lot of training too and it's harder to replicate as it seems in the tutorials ^^
But most minis that follow the "classic" route of basecolor -> wash -> drybrush look exactly like that.
But don't get me wrong, I don't mean to say that those are bad techniques (since there is no such thing) and that you shouldn't do it. But in their standard approach they are a quite limited and you won't develop really neat brush control if you wash and drybrush every mini you paint.
Edge highlights and darklining
both require quite some brush control but have a strong impact on the overall look of your mini. The idea behind edge highlights are as the name implys pronounced edges of the mini where light hits. Darklinings are the opposite. Those are strong, though thin shadow lines seperating different parts of the mini. Combined you already get a lot of contrast and 3D look and a very clean, neat result. GW uses both a lot on their boxart and painting examples.
On really pronounced edges on the model edge highlights are relativly easy to do by using the side of the brush. If you got the right color consitency and not too much paint on the brush you can pull the side of the brush over an edge to leave a very fine line. The pressure on the brush has to be very light though, barely thouching the edge which requires some training.
Drybrushing with a highlight color kinda does the same since edges and pronounced parts catch most of the color but it is not very controled and often looks "dusty" as mentioned. Edge highlighting and darklining on the other hand are very controled and lead to a very clean look.
Of course there are a lot more techniques out there but I think learning to control the brush and paint is quite enough for the beginning. There are endless many things to learn. Theoretical stuff like color theory, how light behaves on different objects ... as well as different painting techniques.
It's tempting to watch countless tutorials and setting your goals very high but you should always remember that the guys showing these tutorials are painting miniatures for years. Like everything it takes time and training. Some progress faster, some slower. Could be compared with the gym. You don't go to it for a week and expect to look like Arnold after a month
But that doesn't mean you shouldn't try things. Trying things is very important! Be realistic with your expectations though.
but I don’t want to do it yet till I get better
Paint what you like and what inspires you! I was thinking that too but there are countless great models out there and that mindset can lead to a kind of burnout. Of course you can paint countless "training miniatures" before touching a model you really like but it shouldn't become a chore! The most important thing is to have fun painting. If you loose fun over painting test minis you don't really like, chances are you'll never paint the mini you actually wanted to paint and trained for in the first place.
So if you're really looking forward to paint a model, do it. You'll get the same learning experience while having fun.
Worst thing that can happen is that it might not meet your expectations but it's not the last cool model that you will paint. There are countless great models out there. And even if you screw up terribly, just buy another one at a later point. Some people also remove the paint from models they painted earlier but in my opinion it's way more fun to see your own progress over the years when you keep your old models. Sadly I have very few of my old models left and collected more minis over the years then I could probably ever paint.
Nearly everyone thinks that way in the beginning and even after years of experience but it isn't really leading anywhere. You will always become better and there is no definitve point where you can say "Now I learned everything and am a pro painter on the pinnacle of skill, now it's time for my final maserpiece"
TLDR:
train brush control and how paint behaves. I would focus on clean base layers and basic layering with highlight and shadow mixtures. Maybe build/buy a wet palette and try it out altough of course no must have. Try darklining/edge highlighting when you start getting more comfortable with your brush and paint consistency. Try what you want and what you think might be interesting and fun but be realistic with your expectations.
And most important: have FUN painting