BBKA exam section is
Here and the Basic Assessment Syllabus can be found
here
The basic is a practical assessment. Could be on your own bees or at your association apiary or the Assessor's for that matter.
It's a pretty straightforward exam to get through, know your bees, times from egg to larvae to capped to emerging. Have a read up on honey labelling recommendations and know your diseases. Believe the fickle might want to know the latin names, but know the 4 notifiable conditions (AFB, EFB, Small Hive Beetle and Tropilealaps), what the signs are, what to do if you think you find it. Have a general idea what the local forage is in your area and what treatments you're applying for Varroa and why and you should be fine.
You might be asked to make up a frame, demonstrate you can keep your smoker alight and take a sample of about thirty bees (matchbox, jar or any other container will do).
[edit] if you can't link to websites, why not just disable the URL feature?
its at britishbee dot org forward slash examinations_and_assessments.php
There are written exam modules too, I did the General Husbandry module this year. One of our associations ran a workshop where we all worked through the syllabus together, if yours is doing something similar I recommend it, I found it very helpful.