How can I update my bathroom wall?

I would remove that tile and put up ship lap or beadboard! Or if you don't want to remove the tile you can paint over it!

If you can't completely remove it, I would try to cover it. You can see how I did it in my bathroom here: https://thehoneycombhome.com/floor-stickers-in-the-bathroom/

I'd be tempted to work with the tile if it's coral as it appears in the photo. If it's red, I'd have to part ways with it. To brighten things up, paint the black trim white. From another website here's the paint recommendations for tile:

1. Latex Paint: Apply one to two coats of a bonding primer that’s made to adhere to surfaces such as tile. Allow the primer to dry for the recommended time, then follow with two topcoats of acrylic latex wall paint.
2. Epoxy Paint: Apply two coats of a two-part epoxy paint that’s made for tile and other hard to paint surfaces, such as Rust-Oleum Tub & Tile. Follow the directions carefully, and allow the recommended drying time before using. The colors available for epoxy paint may be limited.

You could have fun with the top part that's currently baby blue with a paisley pattern in complimentary colors to coral or paint it white to brighten up the room.

Hi Marilyn. I'm Cindy. I would get a stencil and paint over the tile for a complete new look. You can purchase stencils at Home Depot, Lowe's, Hobby Lobby, Michaels, Target, and on line too. Go on line and browse thru some stencils at your leisure. I'm sure you will be able to find one that you like. Practice on a piece of cardboard first until you're comfortable using a stencil brush. You can completely change a room with new patterns and new colors. Your tile looks to be in very good condition. Use that to your advantage. Wishing you all the best Marilyn.

I too would try using ship lap, but if you don’t want to get rid of the blue, or use a lighter turquoise on the wall above and bead board and use a light gray chalk paint on the bead board! I think that would be unique!

Wow. It looks like plastic tiles. Sand, prime and paint everything white. Add your favorite color with towels, throw rugs, and shower curtain.