Yes, you can say a crack free surface. Or the surface has no cracks, the surface did not have cracks. It will depend on the context and tense.

Yes a surface free from cracks is correct. There would be other ways to say this but it would depend what surface you were talking about, a cake, a piece of wood,, a planet 😀

You can also say "A surface free of cracks"

I might also suggest you could say “unbroken” - for instance, “a smooth, unbroken surface.”

"A crack-free surface"