This is a great read and very helpful, written by an ex-FBI guy, I actually should re-read it, its been a while
“What Every Body Is Saying” is a good start.
What Every BODY is Saying: An Ex-FBI Agent's Guide to Speed-Reading People https://www.amazon.com/dp/B0010SKSTO
Here's the book I read to learn about body language: What Every Body is Saying. Very good book, most of the first half is very relevant.
The keys here are
be able to look at their body language and see if they are interested (leaning forward is a good sign. facing away or to the side is not.) What every body is saying is a decent book on body language.
be able to structure it as a story which conveys your emotion to the other person. Charisma on Command has lots of good videos about different possible styles for doing this.
be able to connect your experience to things the other person is interested in. Clearly you don't give a shit about golf.
The last point is particularly useful because it tells the the person that you've been listening well enough that you can predict what they connect with. It gives the other person a jumping point for them to talk about themselves and for you to listen.
What Every BODY is Saying: An Ex-FBI Agent's Guide to Speed-Reading People