Body Language’ is a basket definition for physical responses. It ranges from glancing away to falling silent when another passes, to the fearful arm crossing.
If you watch the people attending a sporting event, you can ‘read’ how they feel about every action on the pitch. They aren’t conscious of their actions, they are focused on the game before them.
Notice those leaning forward, those who can’t stay still, those whose facial expressions are constantly changing.
Learning body language in this fashion will help you in every day life. You want to view people when they are not conscious of themselves.
Watching people in bars or cafes is another training ground, although many will ‘put on’ a particular role when they are in public, judging and being judged.
There is a lot to body language.