get the MB oil filter tool, I paid around eleven dollars. that plastic cap spins off and the filter snaps off the plastic cap, there is a rubber gasket that comes with the MB OEM filter. There is also a copper gasket for the drain plug, if you use that method, and not a suction device.
On my car the oil filter cap leaked and I purchased a new one for a few dollars at the dealer.

I have the same car, really nice. The Haynes manual is a UK version but is I believe essential and helpful.