Am I being scammed from Forex-Billionaires.com?

Has anyone used Forex-Billionaires.com? I invested in BTC and am now trying to get a withdrawal. I gave them my CashApp wallet address but now they are saying I have to let them generate a private key for the funds to be attached. Of course there is a fee to pay. I generated my own private key and Bitcoin wallet and sent the public key. I am reading that you never share your Private key. So I assumed that meant not letting the exchange generate a private key for me as well. Does anyone have any advice for me? Exchange is saying that it’s an empty key and they have to generate it in order to add the funds from the trade account. Does this sound right? Read that the private key is created first and wallet created from the key. So that is why I generated my own. I appreciate any help because I think I might be getting scammed.