Is it permissible for me to accept free grants offered by "Takaful Insurance," which is based on monthly subscriptions from workers and provides compensation for retirement pay and treatment, as well as grants for things like Hajj and marriage?

There is no blame on an employee for participating in the compulsory insurance imposed by the state, even if it is a forbidden commercial insurance, or if its funds are deposited in usurious banks, because he is compelled to do so. There is no blame on him for taking what results from it, such as a pension, treatment, or gifts, even if they exceed what he paid, because the state is responsible for its citizens.