my step son needs to know how to get a scope............can anyone tell me??? thanks in advance

some vendors sell mods for weapons thats how you would get a scope but not every weapon has a scope as a mod

It's somewhat random on vendors. You can try checking the vendor later. I have noticed it seems to be rather easy to get different mods to spawn by backing out to the main menu and then loading the save game over again. If you don't go back to the main menu it doesn't seem to work.

Gun Runners has a lot of weapon mods, I'd check there often. They change every 48 game hours or so.