You can get mil replacement powder from a pet shop or agricultural merchants. Or you can use warm evaporated milk diluted. At two weeks they should be able to lap it from a saucer, just put a drop on the end of your finger to get them to lick it, then put their head down towards the saucer, and when they feel it on their nose/mouth they should start to lap. After a day or two on milk try introducing some kitten food soaked in the milk, then gradually reduce the milk content and feed it separately. The other thing you will need to do is to get a warm damp flannel and gently rub under their tail, to stimulate them going to the toilet because it feels like their mother's tongue licking them clean.