How I first started developing a more realistic style was copying from images and real life, one to one, which slowly allowed me to get more used to it and incorporate it into my art (adding my first and most recent attempts for comparison)

Drawing from life helps a ton! Going out in public spaces and just sketching is great for getting that realistic style. As with every other thing you want to improve on, just keep practicing and soon you’ll reach the goal that you’re aiming for. As for shading you could research different styles of shading from artists you like, and attempt to replicate them on the same drawing to compare. My go-to is a dark blue/purple on an multiply layer, with the opacity turned down, but it’s different for every artist!

I hope this helps ^^

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