First, you need to know how to draw really well. Start with art classes, figure drawing, drawing from life, gestures, drawing and capturing emotion and action quickly.
You'll mostly need experience in boards. Dreamworks features or TV? Boards work differently for TV and feature films.
Don't know about that one.
I don't know of any storyboarding schools, but there are animation schools of course. If you're into TV boards, then 2d animation is very similar in how it works.
A sketch pad and pencils.
Any Cintiq will do, honestly. Whatever size you're comfortable with.
My buddy Mark Simon wrote this book. It's mostly boarding for live action, but most of this would apply to feature animation as well. Again, TV boards work differently. They're more like 2D keyframe animation. Storyboards: Motion in Art, Third Edition https://www.amazon.com/dp/0240808053/ref=cm_sw_r_cp_tai_QgOkDbQVXHSRT

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