Plex is an outstanding media server for streaming your movies, music, TV shows, and photos across your home network from virtually any device. As someone who's managed Plex setups for years, I can attest to its reliability and power.
One standout yet often overlooked feature is remote access, letting you enjoy your entire library from anywhere in the world. It's a game-changer for frequent travelers or anyone away from home. Best of all, you don't need a Plex Pass. Check out 5 Reasons You Really Don't Need a Plex Pass for more details.
Configure everything through the Plex Media Server application—not the Media Player app—to access the right settings.
Navigate to Settings > Server tab > Remote Access in the left panel.

If your router supports NAT-PMP or UPnP, simply click Enable Remote Access. Otherwise, manual port forwarding is required.
What is port forwarding and how can it help?
Return to Settings > Server > Remote Access, check Manually specify public port, and enter a port between 20000 and 50000. Plex defaults to 32400—stick with that for simplicity.

Now, log into your router's admin page:
If issues persist, visit the Plex support site or check for double NAT setups: What is Network Address Translation (NAT)?
Do you use Plex remotely? Share your experience in the comments below.