Every VPN is different in terms of their security features, speeds, and network size. Some cheap services might offer port forwarding, while others won’t. This is a pretty advanced feature, though, so it’s worth asking yourself whether port forwarding is something you really need.
Unless you’re hosting a game server or are experiencing incredibly slow speeds, we’d actually advise against using port forwarding. This is because you’re effectively opening up your device to external connections: this is useful for things like accessing your PC remotely, but it does give attackers another avenue for compromising your system.