The lectures (and notes) cover everything needed to be able to pass the exams well.
The Revision Kit is certainly essential because practice at past exam and exam standard questions is vital.
You do not really need a text book. If you have one then it is best used just as a reference book for any areas you are unclear about. If you do not have a text book, then ask in this forum if there is anything that you are not clear about and I will explain 🙂