I am not a computer expert, but with the right indications I can move easily.
Get to the point, I have a TP-LINK modem with OpenWrt installed on it and the other day I wanted to play Call of Duty, via PS4, with a friend of mine in America (I'm in Europe).
I think my problem is the IP, how can I make my console report that it is connected to a "fake" network located in America?
I apologize if this is not the right section,
Thank you all for your attention and I apologize for my bad English
As @lleachii mentioned, you will need VPN. That world require you to subscribe at a VPN provider (prices vary greatly), and also install VPN client on your router (plenty about that on the forum and the wiki).
Some VPN providers offer trail service, and some offer money back guarantee, so you can try and see if it solves your probablemente and if it's worth the money.