Is the new drivers CPC just the same as the managers CPC?
No, they are completely different things.
If I go for a B+E test do I need an Instructor with me or can I just turn up on my own?
You will need a person with you who has held this category of licence for at least 3 years.
Do I need to pass a medical and theory test before taking a B+E test?
You will only need to have a full Category B licence prior to taking this test. A medical and additional theory test are not required.