ok after i upgrades to xenforo media gallery from xenmedia gallery i see that that gallery moderators permission are present in the usergroup section AND in moderator section, the usergroups are set since xen media gallery was on but do i have to set the moderations permissions in the mod section too ? and why they exist in 2 places ?
This is essentially the same way it works with all XF permissions.
If you have a moderator, and they are added to a certain user group, they will get all of the permissions for that user group. If they need additional permissions that the user group doesn't have, you can add them to the moderator specifically.
So, short version, if the moderator is already in a group that has the permissions, you do not need to add them again in the moderator section.