In the doubly linked list, the next pointer of the last node points to the first node and the previous pointer of the first node points to the last node making the circular in both directions.
Insertions and deletions in a circular linked list are the same as other linked lists. You just need to keep track of the last link while performing operations on either end of the linked list.
You can look up and try implementing Circular linked list using Circular Linked List Algorithm as a guide.