So, I think you are being a bit too hard on yourself. You gestures are what I would expect from someone learning and they aren't that bad
frustration with your progress is something we all face and you will always have something you want to be better at.
I would say just keep trying, keep doing, your work isn't bad at all.
Also become better at controlling the pencil, do circles, lines, boxes all freehand and slow with an intention on being precise
hold the pencil loose and draw from the shoulder
also, I haven't seen proko's gesture videos but I learned from glen vilpu videos, they are kind of old but its a traditional old school class setting where you are watching glen draw. You can see the way he holds the pencil and how he draws from the shoulder which was really beneficial to me. His body mechanics of how he laid his lines down helped a lot!
One of his lessons was just focusing on a flower sack or a kind of oval water ballon type of scenario. Imagine you have a squishy oval typ sphere and imagine how it would look if you put a gentle twist in it. Then lay down a center line of action and then gently frame the shape with curves to fill out the volume; making sure you overlap where the forms are laying in front of each other.
Hope this helps and keep drawing
Keep doing what your are doing, most of this isn't bad at all and looks like you are on your way to becoming a great artist.
From the looks of your current progress you might focus on some drafting exercises to learn decisive line control and perspective.
If you really want to dive deep into this you can check out a really great book on drawing and perspective by Scott Robertson called "how to draw - drawing and clutching objects from your imagination" . Really great! Highly recommend.
if you want an overview of this or something less in depth (but also really helpful) try "modern day james" on YouTube. There are some great videos on draftsmanship and excercises that really inspire
Also one more, there is a website called 'drama box' that has tons of resources for daily practice to get better at controlling the tools we use to create with.
The biggest improvement I can see that you can make with the samples given is a better understanding of 3 dimensional volumes. I practice drawing cubes, spheres, cylinders etc and overlapping them, trying to envision drawing through and maintain size of shape, volume etc all in perspective.
this daily practice for just a few minutes before you draw everyday will show an amazing increase in your ability
I also noticed on one page you were drawing with maybe a brush pen? And the line thickness may be getting in your way a bit to finesse the shapes etc.
I would suggest you keep using this but only to get better with the tool and dont be too hard on yourself when it comes to critiquing the drawing as different mediums that are new or foreign to us might not be the best judgement of our overall progress. Try only to critique your work from tools you feel competent with
but be brave and dont get discouraged with different mediums just because you aren't getting the results you want, because that's the point. Keep doing it!