Shoulder pain around blade. How do I stretch that out?

Good Day!!
First of all you have to make sure what is causing your pain.
I would totally try normal and easy stretching like pulling head opposite side, arms stretching to the front, back and side.
Let me give you this link I found really informative.

https://www.healthline.com/health/shoulder-blade-pain#_noHeaderPrefixedContent

Good luck!!