So i created my group i then add a prefix to it, but the problem happens when i not only see the prefix but also the group name. How do i get rid of the group name, but still get the prefix in front of my name?

Entirely up to your chat format and chat plugin.

Btw. you can’t tag issues.

Entirely up to your chat format and chat plugin.

^^ - LuckPerms just provides the data to your chat plugin when requested. If it isn't being formatted the way you want, you need to dig into your chat plugins configuration.