Is it considered forbidden to stipulate not having children in marriage, especially if one sees himself as incapable of raising and caring for children in accordance with Allah's commands?

Allah has blessed us with the favor of marriage, which produces children, and the Sacred Law commands marriage to the affectionate and fertile.

Having children is an intended purpose of the Sharia, and any condition that invalidates it is void. Therefore, the wife does not have the right to stipulate not having children in the future, and if she does stipulate it, the husband is not obliged to fulfill it, and the marriage remains valid.

Your fears before marriage will change when Allah places in the mother's heart love and affection for the child.