Edited Removing tile from bathroom walls

If the walls are made of drywall you won’t be able to remove the tile without ruining the drywall. If it is some brand of backer board you will need a lot of luck, but not as much as with drywall.

I'm not sure that's possible. I'm sorry!

Unfortunately, mastic, a type of glue, is used to attach the tiles. There is really no way to get them off without damage to the tiles. The only possibility I can think of might be to use a jig saw around each tile and take the drywall with it. You *might* be able to then remove some of the drywall from the back, but you won't have a really usable tile, due to the mastic that will still stick on the back. Of course, then you'll have to replace the drywall. :(

https://www.wikihow.com/Remove-Wall-Tiles

http://homeguides.sfgate.com/remove-bathroom-tile-damaging-plaster-walls-20304.html

http://homeguides.sfgate.com/remove-ceramic-wall-tile-damaging-drywall-99157.html

This person managed to remove the tile without damage, but normally there is some:

I just removed the wall tiles around the tub area, and could not avoid ruining the drywall.

Did you mean without ruining the tile, or the wall? Either one will be a risk. The tile is often broken with the end of a shovel, then shoveled down the wall, breaking tiles as you try to get into smaller pieces. The countertop would be cleared the same way. Drywall is not expensive for a bathroom. Take good measurements of the toilet base before you go shopping. The closer you get to the original base, the fewer repairs to the floor tile you will have to do. Best wishes, Josile.

Here is a good way to remove the tiles..... https://www.youtube.com/watch?v=VDlEd-6HoGU

I smashed mine with the side of a hammer and peeled them off with a spackle knife. I was able to repair the sheetrock with a couple coats of spackle. The first coat looked really bad, but skim coating a second time fixed the problems.