The same way as you’ve invited them as an admin or a mexico whatsapp number moderator, you can also cancel the invite by following the same process. Also, the person you’ve made the admin must visit the group before they can appear as an admin.
Once you make this member an admin, they’ll have the authority of removing and adding any members or admins and will be able to edit the group description and settings.

Final Thoughts
Now that you know how to make someone an admin on your Facebook group, the right thing to do to save yourself from stress and the overwhelming activities of actively keeping up with the activities of your Facebook group is to add someone as an admin on your Facebook group.
As an admin, do you know you can set up three welcome questions when people join your group and then use a chrome extension to get the data into Google Sheets and your CRM instead of having to copy and paste or screenshot the answers?