Just like any light bulb, the one in your Hotpoint refrigerator will burn out eventually. Keep in mind that you'll need to buy a special appliance bulb that is built heavier so it can withstand the cold inside of a refrigerator. A regular bulb will work, but it won't last very long, and you will be replacing it soon after putting it in.
Turn the refrigerator off by unplugging the unit from the wall.
Open the door of your Hotpoint and locate the bulb holder. It should be at the back of the refrigerator, and will have a plastic diffuser as a cover.
Remove the cover by pinching both the top and the bottom to unlatch the plastic clips. Pull the cover out and away.
Unscrew the bulb from the socket in a counterclockwise rotation, and replace with another appliance bulb. Screw it is clockwise until it seats firmly. The bulb generally will be in the 10-watt to 15-watt range.
Snap the plastic cover back on and plug the refrigerator back into the wall. Open and close the door a few times to make sure the bulb works.
You can find appliance bulbs at home improvement stores, hardware stores, large retail stores and many supermarkets.
Be gentle when you unlatch the plastic cover. The clips could break if you are not.