How do I write a will bequeathing half of my gold and dollars to the poor, orphans, and the needy, and for feeding those who break their fast, and the other half to my siblings and parents, knowing that I am unable to give charity now? And can I donate half to Allah while I am alive by authorizing my mother to give it to the poor?

It is better for a non-wealthy person not to bequeath any of his money, but rather to leave it to his heirs. A will is only recommended for a wealthy person. It is not legislated to bequeath more than a third, due to the Prophet's (peace be upon him) saying to Sa'd: "A third, O Sa'd, and a third is much. Indeed, that you leave your offspring wealthy is better than that you leave them poor, begging from people." It is permissible for a person to give half of his money in charity while he is alive, if he is an adult, of sound mind, and not legally incompetent.