Yes, you can also do that yourself quite well. A concrete grinder costs 100 euros, then buy some filler and apply filler twice + sanding. After that, paint the ceiling with primer and then paint it white.
If you work carefully, it looks pretty good. Instead of painting white, you can also use textured paint to get some structure, then you won’t see any mistakes as easily. That’s how I did it in the basement.
I had the ground floor sprayed by a painter, which I think is the best solution.