A pointer is a data type, not a data structure (although some books with rather loose terminology will define fundamental types such as pointers as elements of the larger set of data structures; regardless, a pointer is certainly not an example of an abstract data structure.)

More pertinently, most C++ implementations of abstract data structures such as linked lists, queues, stacks, trees, and so forth will employ pointers as data members; that is, pointers will form part of the implementation; they are not the implementation itself.

As an example, if you're thinking about implementing your own linked list, you might choose to have a doubly linked version, where each element in the list is represented by a node containing pointers to the previous and next nodes:

template <typename T>
class DLList
{
public:
    // Lots of things
private:
    Node* _head; // Pointer to the head of the list
    Node* _tail; // Pointer to the tail of the list
};

Your node might then be implemented like this:

template <typename T>
struct Node {
    Node* _prev;
    Node* _next;
    T     _data;
};