It all depends on the tile and its condition. Diamond grind the tile, then if the tile is pourus and the grout lines are thin, you may get away with one or two coats of a (reg or sanded) overlay. Then prime and base coat.
If its quarry tile or very dense tile with large grout lines, You'll need grind first then prime and broadcast sand. This sand will help in your next step where you'll need to trowel a polymerized cement at a 1/4 inch or enough to cover the grout lines. Then prime and base coat.
If its VCT, best is to remove it but if you can't, bury it with a polymerized cement.
Or you can skip every difficult step and just go with a single component self drying, easy to color match, no mixing required, 10x more abrasion resistant, independent ghost lab conducted, super easy to use water based acrylic epoxy that dries in minutes. You can get this super product in the next World of Concrete Show. Oh sorry, this product is not worthy of such an event, filled with desperate contractors and snake oil salesmen. No , you'll find it on this forum by signing up for a contest. Good Luck.