Pictures attached for 3 bathrooms, first 2 are from same bath

You can see difference between absolute white and morning glory....if you want to visualize this for your room try it on Asian Paints app to get a clear picture of your room.

do you have the interior designing and finishes finalized? as I mentioned earlier, everything in the room has to be tied together. I cannot give you a colour for the arch if it is going to clash with the window frame job, or the cabinets or the wood. In case you don't, I can help you with that. we offer consulting services, which is basically this, the help on Houzz, in a lot more detail. If you are interested, please connect with me on 9921364291 miloni The Yellow Cushion

They are tiles I feel which had been fixed on top...so its difficult ot paint of tiles , just try ot polish them with a polish liquid ...if you need a different looks ,then you need to remove the existing tiles and paint whatever color you want...but for fountains and water surfaces , try ro avoid paint as the paint degrades ...