(2) My cousin is a hair dresser and works in a parlor where he mostly cuts hair of females. Is it halal for him to earn his living through this?
بسم الله الرحمن الرحيم
(1) You should do true and genuine taubah from what happened during the period of 23 years. Your father should adopt such a business or income source which is purely halal and lawful.
(2) It is unlawful and haram for a male to cut the hair of a female and cut it in fashionable style and the income earned through it is makrooh. He should search some halal job as soon as possible and then quit the profession of hairdressing.
Allah knows Best!
Darul Uloom Deoband