
A is the oil drain plug and B is oil return for the turbo? I know, it's as basic as it gets


I have to do an oil change as I've had all sorts of pressure/buzzer issues since a service at the garage and I can't trust the dipstick for levels. Not sure what oil has been put in either.
If I'm changing the oil and leaving the filter on, how much oil should I put in, or should I just change the filter too?
Thanks