Cats' behavior often arouses curiosity, especially when they make seemingly strange moves. One such example is a cat kicking its own face with its hind legs. This behavior actually has its reasons and purposes.

Cats are very clean animals, often spending a significant amount of time grooming themselves. Kicking their faces with their hind legs is one way they groom their facial and head fur. This helps remove loose fur, dander, and other debris, keeping their skin clean and healthy.
Cats have special glands on their faces, such as the submandibular and parotid glands. By kicking their faces with their hind legs, cats can stimulate these glands, helping to secrete pheromones to mark their territory or increase their comfort.
Cats may experience itching or other discomfort on their faces, and kicking their faces with their hind legs can help relieve this discomfort. Additionally, this could be a way for them to cope with skin problems, allergies, or other facial issues.

Cats need daily stretching and exercise to maintain their flexibility and health. Kicking movements help stretch the muscles in their hind legs, increase joint flexibility, and also help improve their balance.
In general, it's normal for cats to kick their faces with their hind legs, possibly to groom themselves, stimulate glands, relieve discomfort, or stretch. However, if this behavior is too frequent or intense, it may be a sign of discomfort or anxiety in the cat, and it's recommended to consult a veterinarian for further examination.