Kiera GraceProvidence Hadfield 5 Tier Ladder Shelf, Leaning Bookshelf Storage Rack for Home, Office, 18" x 67", Espresso

Is there a installation manual? My package arrived without one

Would this shelf work if placed on top of a carpet?

does the bottom of this have stoppers ? will it slide and fall if i place it on hardwood ?

How tall is the space between shelves? is this sturdy enough to act as a lego display case? (think the kid version hogwarts castle, a space shuttle)