Are you wanting to refinish a table top? It all depends on what your current table top is, do you have a picture?
Finish with stain or paint? Is it raw now or what kind of finish is on it currently. Need more information please.
If you are happy with the paint or stain, then apply 2 - 3 coats of polyurethane to protect it.
There are many different options. Are you looking for a flat/matte finish or a glossy finish?
Hope this Helps! Jeremy - https://do-daddy.com
Check out this post I did about how I finished my table top.