Can I add a thin layer of cement to my concrete foundation?

Check out these articles:

https://www.wikihow.com/Add-Concrete-to-Existing-Concrete

https://www.concretenetwork.com/concrete/fixing/overpouring.htm

If the nail holes and the stuck on glue are the only problems, you could just fill in the holes. Try warming the glue with a hair dryer on a small place and see if that loosens the glue and take off with a scraper.

I don’t know, but I do know concrete will not stick to concrete. I cleaned my basement floor the best I could with a putty knife, wire brush etc. vacuum and washed . The paint covered and blended a lot of flaws. It was not a finished basement, so beauty wasn’t my goal. Did the same in garage, sold my house real quick, buyers liked the clean look.

You can use a latex modified floor leveling cement compound to level the floor.

https://www.google.com/search?q=concrete+leveling+compound&source=univ&tbm=shop&tbo=u&sa=X&ved=0ahUKEwjShf6M_KfXAhUFz2MKHdoeBkEQsxgIJw&biw=1016&bih=642

Lots more vidoes if you click on the link.

https://www.youtube.com/watch?v=GSLMhwHBRnU

Use Self Leveling Compound only needs to be 1/8th inch. thick it will sort out imperfections, do not use concrete it will crack.......

Having only small surface imperfections I would try self- leveling , concrete. As to the glue I would call concrete mfg. to determine if it needs to be scaped off or “goof-offed” or hopefully covered up!

My pleasure.............