Diagnosis
Yes, the interior oven light bulb is replaceable. It's a standard appliance bulb that can burn out over time, especially with the frequent on/off cycles from opening the door.
How to Fix It
First, ensure the oven is off, cool, and unplugged. The light bulb is housed behind a small, clear glass cover on the upper left or right side wall of the interior. 1) Gently press and turn the glass cover counterclockwise to remove it. 2) You'll see a small halogen or incandescent bulb. 3) Carefully pull the old bulb straight out of its socket. 4) Take this bulb to a hardware store to get an exact match—it's usually a 25-watt or 40-watt T6.5 appliance bulb. 5) Push the new bulb into the socket, replace the glass cover by turning it clockwise, plug the oven back in, and test it.
If That Didn't Work
If a new bulb doesn't light, the issue could be the socket itself or a wiring connection. Visually inspect the socket for any signs of burning or corrosion. If it looks damaged, that's a repair for a technician.
Heads Up
Always use an oven-rated appliance bulb. Do not use a standard household LED or a bulb with a higher wattage than specified. The higher heat inside the oven can cause the wrong bulb type to fail quickly or even shatter.