Hi to everyone i'm a beginner in general relativity and i'm trying to understand which term in the theory gives the value for a surface gravity of a star?
Im little bit confused for now and this will help me to clear up some things.

Hi to everyone i'm a beginner in general relativity and i'm trying to understand which term in the theory gives the value for a surface gravity of a star?
Im little bit confused for now and this will help me to clear up some things.
i meant that if i know the theory well, how i can calculate gravity, what is the method
You wouldn't expect to learn calculus in a forum post, right? Well, you shouldn't expect to master GR that way, either.
Get a copy of Misner, Thorne and Wheeler. It's over a thousand pages long. You will not "know the theory well" until you have put significant effort into the endeavour. You will likely have to learn some maths along the way.
You may wish to start with the tutorial posted by Markus here.
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