Way too vague. What type of flooring? Wall color genereally should be the last choice. In the whole house ?I find thta paint has yellow undertone so no gray in the floor . We need to see your space please.

Maple:

Usually choose paint after your flooring choice (and any other fixed elements), however hardwood floors in almost any "traditional" stain would probably work. I wouldn't choose a gray stain (but I would never choose a gray stain). The unstained maple above looks good. As would white oak in nearly every finish from unfinished to dark. Red oak in a medium stain would probably work. Get yourself a large sample (Samplize or a 2x2 ft foam board that is painted) of the paint you want to use and take it to the flooring store. Hold it vertically to the wood. Take the samples home that you like and see how it works in your space with your lighting.

If you're considering tile, that's a different can of worms (too many options). I would choose the tile first then the paint.

You pick the floor first then coordinate the paint with it, not the backwards way you're approaching it.