Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
I answererd the questions if you read them your self - "the Realms owner has to know your game name to be able to send you an invitation", "it is free to play" "player all over the world can join" - and also gave some additional info - why is that wrong?