How do I get information about starting a thrift store with a relationship to a charity like Goodwill?

I was not aware goodwill did any relationships other than own their own.
I do know they sell bult and/or baled clothing and also the larger places have weekly auctions of goods.

To have your own chairity, you will have to form a non profit corporation, and file for legal non profit status with the IRS

Is there some information that perhaps we are missing here? What kind of relationship would you like for the thrift store to have with Goodwill, please?