I just finished ripping up old tile from my fireplace hearth and found that underneath is a very large concrete slab. I then realized the slab is visible from the basement (see attached picture). I would like to lay new tile down but am not sure the best way to make it level. There are some deep cracks/holes that don't go through and one hole in the corner that goes through the entire slab. Any help would be great!
Basement ceiling
Uneven surface
2x2 hole
Basement ceiling
Uneven surface
2x2 hole