These are the sides for reference

Does it have to be tiles? I would not want tile on my vanity? the cuts required will make those tiles look very choppy honestly as almost every tile will need to be cut for the top, many multiple cuts.

Is the base concrete? Seal it and be done.

That should not be tiled. Tiled counters are awful.

First you will need to remove the sink and faucet so be prepared for a bit of a hassle with cutting those holes . Why tile that size ? I do not love tiled counters but it is the tile size i am having an issue with .Waht are going to use for the corners where the tiles meet ? Have you actuallu layed this out to see how many cuts and how this will look? The question you asked tells me you did not think this out before buying tiles .

I ripped out 5 bathrooms with tiled counters in my previous house.

Maybe young people haven't been exposed to (or had to live with) tile counters, and now think it is a "great new" idea that no one has used before! It has definitely been done before and it isn't a good idea!

Tiling a vanity top is not my favorite however this has potential to look really cool. Is this a powder room? What are your plans for edges? What sort of grout will you be using? Are you tiling the face and inside as well?

You will need to remove the sink and faucet to do this properly. I would suggest going in the direction you are showing on the side not the way you are showing on the top.

Good luck!

I thought you wrote that you are tiling a busy vanity, because that is how it will look. Extremely busy with so many cuts and three different facings in such a small place. I agree that the concrete looks really nice. I too would seal it and save that lovely tile for elsewhere in your home.