I'm an introvert. I've also been a CEO. And taught classes on public speaking. Introversion and talking to strangers are not mutually exclusive.
For me though, every interaction is always a race to getting them to laugh, or even just grin. Once you do that, all the tension just drains away.
Watch lots of standup comedians on YouTube. See how the speak and copy their body language.
Also, try asking real questions as soon into an interaction as possible. What do you do? What do you enjoy most about it? What do you need more of at the moment?
Suddenly in the space of 30 seconds they're telling you what their biggest pain points are. Just because you asked.