First, make sure you understand the rules before you join a public server. Small infractions will likely get a warning first, rather than an outright ban. But if you were banned once, keep in mind that NordVPN and Meshnet should not be used to bypass sanctions under a valid Terms of Service, including circumventing Team Fortress 2 IP bans. It’s best to reach out to the TF 2 community and try to get the ban lifted.