Oh, you installed one of those contracts that gives all your money to a scammer.
It's gone. You donated it to a scammer. You can't get it back.
There are only 3 things you can do with this contract besides send it money: receive (which does nothing), withdrawal (which sends all the money to the scammer) and start (which sends all the money to the scammer)
You found some token recovery code on the internet, that you can put in your contract to let you recover tokens, but you did not put that code in your contract so you can't use it to recover tokens, and ethers aren't a token anyway.