Is it permissible to take money from one's father to invest in a private business, knowing that the father is a partner in a restaurant that operates even during Friday prayer time, and he does not respond to his son's admonitions regarding this matter?

It is permissible to take money from one's father for work and self-development, as long as its source is not unlawful. A cook's work during Friday prayer is forbidden, and he must not receive customers during the prayer time and should put up informational signs. Any transaction concluded after the second call to prayer for Jumu'ah is invalid, based on the Almighty's saying: "O you who have believed, when [the adhan] is called for the prayer on the day of Jumu'ah, then proceed to the remembrance of Allah and leave trade. That is better for you, if you only knew." They must continue to be advised.