The five chapters of the official handbook, each as its own set of numbered tests.
The official handbook, Life in the United Kingdom, A Guide for New Residents (3rd edition), has five chapters. Going one chapter at a time lets you test yourself on a part of the book soon after you read it. Your scores then show which parts need more work.
Pick a chapter to see its tests. A numbered test is always the same questions, so you can sit it again and see how your score changes.