RTOS programming is not a beginner's topic and is definitely not the right starting point for learning about embedded systems. If MCUs or the C language is totally new to you, then you're better off starting by covering the basics and getting some hands-on experience before diving into this more advanced topic.
So, who stands to benefit the most from working through this book?
Professional programmers: You've always programmed on bare metal (no OS) and are looking to increase your MCU programming skills by learning how to use an RTOS to meet tight timing requirements, balance concurrent operations, and create modular code.
Students interested in "getting their hands dirty": You've been covering theory, listening to lectures, and coding lab exercises, but now you're looking for a complete guide that helps you to get started with something you can physically touch and interact with.
Makers moving onto more advanced topics: You've written some sketches or scripts, but you're looking for your next challenge. Maybe you'd like to create a full MCU-based system from scratch – the information here will help get you on track for the programming side. You'll even get some tips on what to look for when selecting an MCU for your project.