In the Reminders app, you can create new lists, organize the lists into groups, and pin lists for quick access.
You can have a maximum of nine pinned lists.
To change the position of a pinned list, tap , then tap Edit Lists.
Tap Add Group, enter a name, select the lists to include in the group (optional), then tap Create.
Go to the Reminders app .
When you delete a group, you have the option to keep the lists.
Deleted lists or groups are moved to Recently Deleted. You can recover them within 30 days of deletion. After 30 days, they’re permanently deleted.