Explain please. I have Plex, but have been unable to get port forwarding to work in order to distribute my content outside my home wifi network. Would vpn help with that?
VPN is helpful so your ISP doesn't give you grief if they notice where you obtain your media files.
If you're not afraid of others knowing where you get your media files, it's unnecessary.
PlayOn, for example, is a DVR-like piece of software that allows me to record content from a streaming provider and maintain my own copy of the file. My biggest use for it is to buy something from Amazon, point my PlayOn software at it, and create my own MP4 file that I host on my Plex. You don't want to expose such a file to any P2P file share environments though because it's tagged with your PlayOn license and IP address from which you recorded it. Content producers will come and spank your pee pee with barbed wire over that.
I rip EVERYTHING I buy from Amazon to disk via PlayOn. I absolutely do not trust them to be the sole custodian of my multimedia and sole arbiter of the EULA for it. Go look for stories about Amazon deleting things from peoples' Kindles and such.
Also... look at the Mandalorian Season 2 Episode 4 ("jeans guy") for another example for why owning media is important. Or E.T. If the streaming provider holds your only copy, they can edit it at their whim. I have Mando S02 E04 "jeans guy" edition on my Plex, and Feds-with-guns-willing-to-shoot-children version of E.T. and the Despecialized Harmy version of the Star Wars Trilogy.
Torrenting is a great way to get caught. Don't torrent. And honestly... it's not that big of a deal to buy the content you like.
But if you want to avoid ripping BluRays to MP4 or streaming to file with something like PlayOn, then Usenet and NZB is your friend (double-plus so over HTTPS/SSL). If you own it, you own it and your EULA allows for an archival copy. How you get that archival copy is irrelevant. Go try Easynews.com for a good Usenet provider for such things. If you're really paranoid they also offer VPN services.
As for port forwarding, it's pretty simple unless your ISP is one of the sphinctery types that try to block such behavior. To get Plex to work seamlessly outside though, you're gonna want the Plex Pass, which enables the more advanced distributed streaming features of a Plex server, along with integrated user management and so on. Honestly Plex Pass is the best $75 I've ever spent on software. I must have bought it over 10 years ago and I still get updates for it and the company hasn't come up with a way to weasel out of the "lifetime" portion of the agreement.
My Plex server is every bit as wonderful as Netflix for my family and the handful of people I grant permission to access it. And never a commercial!