Change which groups a user belongs to

On the menu bar, click Users and devices.
In the left pane, click All users.
Search for a user account.
In the search results, click the name of a user account.
Click the edit icon beside Group membership.
To assign a user to a group, highlight a group in the left column. Click the right arrow icon to move the group to the right column.
To delete a user from a group, highlight a group in the right column. Click the left arrow icon to move the group to the left column.
Click Save.