The said person should perform the obligatory prayers from now on. He does not need to hasten to make up the missed prayers, but it is not permissible to neglect such obligations. To make it easier to make up for the past prayers, he can offer – for instance – each obligatory prayer twice: one as his current obligation and one to make up for the past lapsed prayers. He should ensure that the prayers that remain are a part of his will so they can be offered on his behalf after his death. He cannot pay somebody to offer his prayers on his behalf, but his heirs can do so after his death.
Usually they are not trusted to be needy. If one is certain that they are in need then he can give food that satiates them. It is also permissible to give them food if the person knows that they were in need before.