Your course textbook can be accessed via the DART eBook link in the Getting Started module.
Delligatti, L. (2013). SysML distilled: A brief guide to the systems modeling language. Addison-Wesley.
Read:
Chapter 1. Overview of Model-Based Systems Engineering
Chapter 2. Overview of the Systems Modeling Language
Chapter 3. Block Definition Diagrams
Chapter 4. Internal Block Diagrams