Questions on money received

I received ETH into my ethereum extension network. It shows that it is in there but does not show received. It just has a white empty circle next to the amount in assets. It will allow me to send back to the same address that sent it to me, but I am told if I sent it to other addresses, it will take a huge fee. I do not entirely trust the person that sent this money and want to make sure it is legit. Is there any way to fake that the ETH was sent. When someone else sent ETH to the same address it went to the ETH main network and shows as received. That transaction also shows up on etherscan but his does not. I don’t see anything anywehre about how anyone could fake crypto, but at the same time it doesn’t seem legit. Please HELP!