Do anyone know how to replace driver side rear light bulb on 99 suburban?

There should be 2 phillips head screws on the door post. If you loosen these 2 screws you should be able to remove the entire taillight assembly. You may have to carefully pry it off with a flat tip screwdriver as the gasket might still be holding it on. Once that is done, the bulds will be accessable.
They're held in place with a sort of cam-lock. You'll have to rotate the fixture to get at the bulb.
Simply remove the bulb( I think it pulls out) and replace it with a new one. Re-attach the taillight with the screws.
Hope this helps.