1- Both devices must be connected to the same router, with the same workgroup and IP range.Â
2-Â You can access media content on the My Cloud by means of network shares or through the Twonky media server. Shares, similar to folders or directories, are areas set up to organize media and access them from your network.Â
3- It all really depends on your needs, for media streaming the My Cloud is a really flexible device to share your media on the network, it is also a lot cheaper an power friendly than a PC.Â
Have you installed the plex media server on a PC or Mac on the same network? As you need the server running not just the Plex app for Samsung on your TV. Also like said above you can just stream to your TV but using Plex youll need the Plex server installed.