Set up a OpenVPN Server on your own Ubuntu server.

There are several tutorials on installing OpenVPN manually (Ubuntu, Digital Ocean).

However, it’s much easier to install with a pre-written script as mentiond in nixCraft, based on the Nyr/openvpn-install script.

For public IP, you can type in a DNS domain name (requires setup beforehand). Or, you can manually change the IP in .ovpn file to your domain name manually afterwards.

As for the client, download OpenVPN Connect 3.