Pets At Home stock Nature's Menu, which many people start their dogs on, although they mainly seem to change to something cheaper once they're confident with feeding raw. NM do a variety of nuggets, blocks, free flow minces and meaty chunks. Be aware that some of the nuggets contain cooked rice, nothing raw about that!
Before you start, and if you're on Facebook, have a look at some of the raw feeding groups on there. Some are quite extreme and are really for those who feed whole prey, but most are happy to have members who feed the more accessible stuff such as minces. I recommend Raw Feeding UK, which has a start up guide and a chart of how much to feed amongst it's files. It's a good place to start, to do some reading and then ask questions.
Ultimately you want to aim for a varied and balanced diet of around 80% muscle meat, 10% offal and 10% bone. Growing puppies need more food than adult dogs.