If water is leaking out of the spout, you can replace a faulty cartridge by removing the small cap at the top of the valve handle and then remove the screw holding the handle in place. You should then be able to pull the handle off and twist/pry the wall flange off exposing the cartridge. Remove the cartridge with an adjustable wrench and get a replacement cartridge from your home store or plumbing supply store.
If your goal is to remove/replace the entire faucet, remove the handles and wall flanges as described above. The spout needs to be turned counterclockwise and unscrewed from the valve. The actual base will have to be removed from behind the wall, hopefully through an access panel or by removing the tile.