If the filament of the side light in the combination lamp of the left rear lamp has burned out, then until the lamp is replaced, you can continue driving by turning on the rear fog lamp.
At night, in clear weather, the fog light will produce a blinding effect on drivers of vehicles moving behind your car. Therefore, try to replace the side light bulb in the rear light with a working one as soon as possible.
Work to replace the combined side light and brake light bulb (see «Replacing the lamps in the rear light, removing the light»). Replacing the headlight bulb is shown on the left headlight. For the right block headlight, the operations are similar.
Turn the headlight cover counterclockwise (there is an arrow on the cover indicating the direction of rotation)...
...and take it off.
Disconnect the wiring harness from the headlight bulb.
Push down on the spring clip of the lamp.
...and disengage it from the hook.
Set the spring clip aside.
... and remove the headlight bulb from the headlight housing.
The headlight lamp is halogen. You should not touch its glass bulb with your fingers, as traces of them will lead to a darkening of the lamp when heated. You can remove contamination from the flask with a clean rag soaked in alcohol.
Install the new H4 headlight bulb in reverse order.