You might consider a ceiling mural for the tiles. One of the sky, maybe? The cost varies by the area covered.
You could change out the tiles to newer, more decorative ones. You could also paint them or cover them with wallpaper.
We upgraded ours from older rectangular tiles to smooth non perforated square ones. It was a wonderful improvement
Could you paint it? If not here’s a bunch of ceiling ideas that we’ve done: https://www.frugalfamilytimes.com/search?q=Ceiling&m=1
Amazon offers a nice variety of peel and stick Styrofoam tiles that are textured and you are able to cut to fit. These can also be painted.
You can paint and refresh it. OR you can remove the tiles and cover with prepasted wallpaper. I did my kitchen due to a water leak on the 2nd floor. It was beautiful. Simple just cut your wall paper to the right size squares, soak according to package directions apple, smooth and done. Or you could just do a few in the cent of the room or the ones on the edges to make a border. Repaint the metal frames if they are dirty to make it look new.