Yes, you need to have digital copies of the media on the PMS machine, or available through a network connection to the machine.
Yes, you could play the media anywhere, as long as the PMS settings are set up to allow Remote Connections. And your playing device has a WiFi or data plan connecting it to the internet. You also need an uplload speed high enough to support the media bitrates, or a machine with a fast enough CPU to convert the media to a bitrate your connection can support. This doesn’t require a Plex Pass to use, and is available to anyone running Plex Media Server.
You can also set it up to sync the media to your phone when you are on WiFi to reduce data plan usage. For this you need to have a Plex Pass on the server, but not on the individual users you share with. As long as you set them to allow sync in the user details for your Server, they will have the option to sync media.
No, you don’t need Cloud Sync to do what you want to do. I am currently streaming media off my PMS to my GF’s LG TV located about 10 miles away. It works very well. If you use Cloud Sync, it basically uses your server as the transcoding machine, but stores the media on the Cloud. (SWAGGING here, don’t have it set up, and very likely never will.) (SWAG = Scientific Wild A$$ Guess)
Plex Cloud is in an Alpha/Beta stage right now, trying to set up a Plex Media Server and libraries on Cloud storage providers. The actual server in this case is running on Microsoft’s Azure (from what I understand.) In this case, you wouldn’t need to have a server on 24/7 from my understanding. BUT you are going to incur charges with whichever provider you set this up with. Again, this is a SWAG, as I don’t plan on using Plex Cloud either.
Apple Music’s media is likely DRM’d media, meaning it’s restricted to either one device or a few devices that you have enabled on your account. (I don’t know for sure, as I don’t use Apple Music. This is another SWAG.) DRM media is not supported in Plex Media Server, and even discussion of breaking DRM is a forbidden topic on these forums.
Much of the “guessing” I’ve done is through reading posts on these features or knowing how this works with my own setup. You can go to various posts and form your own guesses as to how this can work for you. All you really need to make it all work is a machine to dedicate to PMS, drive space to store the media on, and a fat enough upload speed to support the bitrate of the media you want to stream.
