Hi Mark,
To successfully pass the Life in the UK test, you will need to have good knowledge of the 3rd edition handbook Life in the United Kingdom: A guide for new Residents.
You can buy the book from the recommended GOV.UK site at
https://www.tsoshop.co.uk/Society/Life-in-the-UK/
Alternatively, you can read the online version of the book that is available on different websites online. There are various websites on the internet where you can read the online version of the Handbook and practice the tests. Most are quite good to practice mock tests to prepare for your final one.
Non official web links removed by moderator.
Once you have read the book and start passing the mock tests on these websites, you are ready for the test!
Good luck with your application and shout out of you have any more questions.
Best regards,
B