There are two main drone training courses in the UK: The A2 CofC, for flights in the Open Category; and the GVC, for operations in the Specific Category. The GVC allows you to apply for an Operational Authorisation, similar in scope to the former PfCO.
heliguy gives you the option to sit these courses individually, or you can take the A2 CofC and GVC Combined Course. The combined course is a more cost-effective option and gives you flexibility to operate across both the Open and Specific category.