Create a plex account through plex.tv. There are also options sign up using your Google or Facebook account. You don't need to buy a Plex Pass or pay for anything.
Contact me and ask for access. You will get an invitation link to the server.
Open the link and log in with your plex account. Once logged in follow the instructions.
You're all set you can watch movies through the web player at plex.tv or use your Xbox, Smart TV, etc. Feel free to make requests for new content through Overseerr, you can sign in using your plex username. If you have any further questions feel free to reach out.