Primer Design with Primer-BLAST over specific site
I think various ways can be apply, but the easiest way could be to indicate the range to set a forward primer. 

Decide the length of primer you are going to get. 

Let's say you would like 25 mer. 

You can set the range from chr12:25398261 to chr12:25398309. 

When you identify where chr12:25398285 is in NG_007524.1, you are ready to design your primers.