For a show with amazing fighting, I can't recommend Netflix's The Witcher enough! The sword choreography was beautiful!
I recommend looking at shows and movies with action and using them for an exercise I did in school a lot. Basically, you do a redraw of a scene. It helps you practice pacing and figuring out what needs to be shown (drawn) vs what can be inferred (not drawn but insinuated through onomatopoeia, flow of paneling, etc)
Not to mention, thanks to youtube, this can be done for basically no money required on your end.