Asp.net core has three frameworks.
- mvc, which is mature and does not change much with versions. Mostly binding support changes.
- razor pages, which is the preferred upgrade from web forms. This framework is getting more updates with versions, but the concepts are consistent
- blazor, which is the newest and most changeable. You should learn from the current docs.
Which one will you study most? Your book uses an old version. You may find you need to work to get samples to run. This can be a learning experience, or just frustrating. Depends on your learning style.
what may change most with new version, is the templates used to create a project. the new min api (reduction of boiler plate code), makes the template code different with versions, even if the old style is still supported. Also the templates used to use bootstrap, but trend is not have an opinion on css frameworks.
without knowing your learning style it’s hard to give good recommendations. As they age so quick, I stopped buying books dedicated to a framework.
The real issue is that the asp.net core will continue to evolve, how will you keep up? one approach is the bleeding edge. The other is stick with LTS versions that only change every two years.