How do I remove old floor tiles?

Vinyl ones - with a giant steel scraper/chisel, that has a long handle. It probably has a formal name.

Ceramic- hammer & then chisel underneath & pry/pop them up.

Whether you’re removing mastic adhesive or thinset mortar, that has to be done thoroughly before installing the new flooring.

I use a pry bar and hammer to lift and remove each tile.

You can rent machines to help do this at home improvement stores, by the hour or by the day. These may make short work of a very difficult chore. Best wishes, Jewell.

We did ours with hand tool as well. Pry bar and a hammer. And a lot of patience