Is it permissible for a son to give the price of his father’s land to his mother and siblings, given that the son knows his father attempted to sexually assault his siblings, does not spend on them, does not pray, and curses God and religion?

The father must be advised, warned of Allah, and called to repentance. If he repents, that is the desired outcome. Otherwise, his matter should be referred to someone who can deter him, and he must not be allowed to be alone with his daughters. If the father is withholding obligatory maintenance, there is no harm if the son gives the proceeds from the land to his mother so she can spend from it on herself and her children in a reasonable manner, following the example of Hind bint Utbah with Abu Sufyan. Scholars have unanimously agreed on the obligation of the father to provide maintenance for his wife and children.