My left rear brake light and turn signal do not work

Well unfortunately it’s not quite that simple! .. Since both brake AND signal lights use the same bulb ELEMENT inside the bulb - the brake light circuit MUST pass through the signal light switch BEFORE going to rear lights so they will operate independently from each other while brakes are applied AND signal light is on .. One rear light will be blinking and the other is lit continuously .. Otherwise you’ll have both rear lights blinking and no continuous brake lights. I know it’s kinda confusing but you can not wire around the signal light switch - WITHOUT adding more lights to the vehicle. It will be much more cost effective to repair the existing failure! For that to take place *hands-on* test must be applied.