It all depends on the model number, which you did not mention, so a generic answer is the best we can do.
Some models have customer-accessible covers to allow for replacement of bulbs, some do not. The owner's manual will show you that.
If it's not mentioned in the manual, then you have to remove the outer cover.
If that's the case, on an over the range model, it will have to be removed from the wall first.
You can
download GE
owner's manuals and installation instructions here.
You
can download owner's manuals and installation instructions for
several brands (including Amana, Jenn-Air, Kitchenaid,
Litton, Maytag, Roper, Tappan, Thermador and Whirlpool) here.You should be able to download your LG / Goldstar manual
here. If not, you can contact them via that page to order one.
You can
download Frigidaire owner's manuals and installation
instructions here.You can find links to helpful exploded view diagrams and part ordering help
here.
I recommend that you bookmark that link to your favorites.
We're
happy to help you with free
advice and we'd appreciate your thoughtful rating of our answer.