I think we need a bit more information about your puppy. Have you just got him or have you had him since 8 weeks old? Did his breeder not give you a feeding schedule? What brand food are you using?
If you want to feed a complete food (kibble) get the best you can and avoid cheap, highly coloured versions (these tend to be the heavily advertised, supermarket stocked ones) Good advice is to be found at an independent pet shop, not big ones who will push their own products which may not be best for your pup.
All kibbles have a suggested feeding schedule on the bag to give you a rough idea of how much and how often to feed.
We use Arden Grange but other people will be able to suggest other, equally good brands. As for chicken, our boys came from their breeder already used to eating raw chicken wings so 14 weeks isn't too early at all. We feed kibble for breakfast and raw for supper. Again pet shops will have a selection of raw, frozen foods in their freezers.
