Do I need to own a game to use insider?

You need to sign in with the account that owns the game
This means that you need to use the "Sign in with Microsoft" button inside Minecraft launcher

Hello Aquarrz,

Also if you are in the insider program, you would need to go to the insider forum. This forum is for the general public that don't have the updates that insider get. This is the reason the insider program has its own forum. I will do you a favor I will lock
this thread I will re-open the other and then change it to a discussion for you.

Thanks,

Brad

Why oh why do I need to do this inside a game instead of an option in the GFWL marketplace somewhere? Needing to download a game on PC to change gamertag for use with phone = really stupid

Game Pass Core (at the least) is required to play online in all games with the exception of free-to-play games.

Hey there,

Are these disc based games you own, or do you happen to be game sharing with a friend or family member who owns these games digitally? This error normally pops up when the owner of the license is not signed into the Xbox One console, or if it is a disc based
game the disc will need to be inside the console. You can check the games you have purchased digitally through our
Microsoft Commerce page while signed in to make sure you own the games in question.

Keep us posted!