Can you tell me how to manage the hypertension of my father?

Hypertension: You should make sure your father is under the care of a good physician. He may very well need one or more medications at least as a bridge. If he is overweight, then normalizing his weight could help. High blood pressure is generally the result of multiple issues adding up. Sleep apnea is a common cause of hypertension, so treat it aggressively. Decrease sodium intake. Exercise.