You don't need exercises: The book is a step by step "instruction manual".
There is only one exercise (in this context; there are many other forms of meditation) Sit comfortably. Breath in. Breath out. Repeat. Now gently try to let go of your thoughts, and gently focus your attention on your breath. When your mind slips, bring it back to the breath. Repeat for as long as you want to sit.
The reason you want to read the book is because it deals systematically with the practicalities, such as how to deal with pains and aches and distractions, or how to deal with sudden intense nonsensical urges (for example, when I started I went through a period where I'd get one minute or so in and then be convinced that I'd failed to set my timer, and that I had been sitting for way too long, and that I'd be late for something, anything; it took weeks to push past that barrier).
I'd also strongly recommend this series [1] of recordings of a course by Gil Fronsdal. It covers the same practice, and fits very well with the book. And like the book, the course recording is very much kept secular.
Does your book contain exercises?