Here is one way that might be helpful - https://www.remodelaholic.com/under-100-carpeted-stair-to-wooden-tread-makeover-diy/
I've always loved this idea: https://www.hometalk.com/32855202/30-minute-stair-makeover
It uses decals, but I've seen people paint numbers on the risers or cover them with wallpaper. Lots of pretty ways to decorate them depending on your style.
Thank so very much