/ic/ - Artwork/Critique

How do I get good at drawing? I'm left handed, have perpetually shaky hands, ADHD, autism and a learning disability. Almost 24.

I've wanted to get good at art since I was a teen but I've lacked the motivations, resources and teachings to get started.

I don't know
>which brush size to use
>optimal size to draw digitally
>good pressure curve to start out with
>how to find a comfortable pressure curve
>how to undo bad habits like drawing stiff figures
>how to fix shitty lines you're too used to drawing
>how to get better when you're experienced but /beg/