Port forwarding on Linux Mint

[RubberSoulWarrior 0]

Hello, I am not tech savvy so im sorry if I missed something obvious. I was using airvpn on windows 10 for qbittorent, but yesterday I switched to Linux Mint cinnamon on my laptop, I have never used linux before so I'm very new to this. I downloaded airvpn using .deb and installed it, the VPN itself works fine and there are no ip leaks. But when I set up a port on qbittorent, when downloading it shows that there are no direct connections and when checking the port in client are it shows a TIMEOUT. Looking online I figured it has something to do with Linux network configuration/firewall. Looking in network settings at eddie it shows that Fwmark is off, I tried changing it to 1 but after doing that it just copies the network in my settings but with Fwmark still off. Could someone tell me what I'm supposed to do in network settings or how to set up firewall rules properly? As I could not find any instructions on the internet how to do so

[Tech Jedi Alex 1515]

While connected, bind qBittorrent to the tun0 interface and restart qBittorent.