Any Suggestions for Gentle Exposure Therapy for Rejection and Embarrassment?

Does anyone have tips for how to gently expose myself to Rejection and embarrassment? Also, what do I do with the intense feelings that arise? How do I make sure that the Rejection exposure isn't causing more harm?

While watching a k-drama series today, the ML made a mistake which caused a lot of embarrassment and I FELT THAT EMBARRASSMENT DEEP IN MY SOUL. I've stopped watching for now but it got me thinking about how I don't really know how to handle embarrassment or rejection so for the most part, I've kinda hid from the world. I want to be able to handle embarrassment a bit better and maybe stop retreating as much into my cave.

I'd really appreciate any Suggestions or tips. I probably wont be able to chat up a stranger right off the bat so would love some sort of gentle starting point.