lost 3.4 eth, was actually scammed, how can I report scammer/find him(and or kill)?

I have the etherscan of him sending me Test Eth and claiming it was real in order for me to send him the instagram account he was purchasing details. I had no idea test Eth was even a thing. So I sold it to him and now realised. What can I do? (I’m not going to actually kill the scammer🤦‍♂️) just want him caught and make sure he can’t ever do this again.