You take over a project that is already in trouble: the money is mostly spent, the sponsor has stopped coming to meetings, and nobody can show you who approved the last three changes. PRINCE2 is built to stop a project reaching that point. To be certified in it, you pass PeopleCert's PRINCE2 Foundation (Version 7) exam: 60 multiple-choice questions in 60 minutes, closed book, 60% to pass, and no prerequisites.

This guide starts with the failing project, because that is the fastest way to see why the method is shaped the way it is. It then covers how PRINCE2 certification works, what the seventh edition changed, how the Foundation exam is run, the order in which to study, the terms that trip people up, how renewal works now, and where Foundation fits beside Practitioner and PMP.
What would PRINCE2 have caught on a project that was already failing?
Go back to the project you inherited and ask a simple question at each point where it went wrong: which part of PRINCE2 would have raised a hand? The answers map almost one for one onto what the Foundation exam tests.
The business case nobody reopened
Most failing projects were justified once, at the start, and never again. The costs grew, the expected benefits shrank, and the project kept going because stopping felt like admitting a mistake. PRINCE2's first principle, continued business justification, requires the business case to be checked at every stage end. If the case no longer holds, the project board changes it or closes the project. A project that is allowed to die early is a PRINCE2 success, not a failure.