There are great video series on YouTube, for example:

https://m.youtube.com/@pbsspacetime

https://m.youtube.com/@HistoryoftheUniverse

I often find videos easier to follow due to the great visuals.

You can also listen to interviews with the authors on podcasts. They talk about their books and the concepts in them.

And as always, your favorite LLM is a great companion to help you understand. I've consulted it several times and the answers and links it provided were very helpful