Thank you for reaching out! Unfortunately, you can only join with a premium (purchased) Minecraft: Java Edition account. If you want to play and have access to such an account, you can connect to the IP play.potterworldmc.com. We support any version between 1.10 and 1.13. However, version 1.12.2 is recommended. Sadly, the Xbox edition of Minecraft is not the Java Edition.
I hope this answers your question, and please let us know if we can help you further!