I think there's an oil leak coming from the rear driver side of motor

What is your question?

I have recently had an issue with my vehicle loosing a little bit of oil is coming from the rear driver side of engine it kind of looks like is coming from a allen head bolt or the around plastic cap thing on the back of the valve covers the car has overheated one time when the radiator blew any ideas do I need to replace the head gasket or what