In 4.2, many tools are now found in the Edit > Preferences > Get Extensions menu.

: Use nodes to change colors, materials, and lighting post-render. Availability and Official Sources CORE Fundamentals: Unlock the Core of Blender

You have a part of a highly recommended beginner series. If you are new to Blender, is the perfect place to start. It strips away the complex technical jargon and focuses on the "core" skills you need to actually start making things.