Help please!

[night raptor]

I love to draw, it’s literally been one of my favorite things to do. But I honestly suck at it. I watch tutorials, practice, learn, and do everything but I also take month breaks in between because I’m so busy. I’m constantly frustrated because I can only draw heads up, even shoulders are a difficult thing for me and most of the time I end up having to reshape heads, and fix everything the way a face is structured and it irritates me badly. I added some examples and the sketch I had just made probably 2 minutes before creating this message. I try to study bodies but somehow it just never works, and I can never actually understand anything. If there are any tips on just my drawings I attached alone, or how to actually understand coloring, shadows, anatomy, anything please share. I do both digital and paper so literally any knowledge you have would be such a great help to me.

These are only a few art / art styles I really enjoy! I also attached a few more of my drawings to emphasize how I can literally only draw heads & up lol

[visual wind]

Hihi! I am not a pro by any means but I've been studying anatomy again recently and have some tips that helped me personally!

From the third picture you posted I think that the box guides you drew feel flat on the chest and perhaps doing a perspective box drawing exercise would help with the 3d aspect (just until you feel confident in being able to do 3D boxes).
I personally looked up anatomy boxes and just copied them, trying to retain their methods. It is tedious and boring but I think it definitely helped to identify the shapes needed to make up the body!
Looking up pose references and giving 6 mins to draw starting from the boxes helped me ( try to vary poses, body types etc. don't dwell on neatness just try get the whole pose done, shading helps alot to show the intentions). Whilst I think it should be done multiple times don't force yourself, art should be fun after all. Also I recommend avoiding references that have alot of clothing like the third picture you posted as you want to learn the base of the body and the clothes make it hard to see how certain parts should look.

I like the faces you showed so maybe if your bored of the same stuff switch it up by drawing them! And if u still want to learn maybe try different expressions etc. Goodluck!!