How to use a server as an intermediary between two clients?

Question

Computer networks

There is my computer, raspberry pi and server (vds). A vnc server (tigervnc, because arch linux is on it) is configured and running on the raspberry. On raspberries and on my computer, IPs are dynamic, so I can’t connect to raspberries from a computer outside the local network. But there is a server with a static IP.

Please tell me what to google, how can I connect the server to the raspberry, so that through the server I can access the raspberry ports, or at least the port with the vnc server? Is it even possible?