well, I can’t really “give art advice” globally for your game, cause that’s kinda vague. I can however give you tips on individual things that you want. generally, I’ll say that your game’s art has a lot of room for improvement, you might want to make the characters not the pixel art version of stickmen
this is a body type that’s easy to make, but I’ll say it straight up, it looks really bad. arms and shoulders don’t work like that, it looks weird. try to make it look a little more realistic and make your character strike up a more engaging pose.
If you would like help on specific sprites, lemme know, I’d be happy to assist (: