What do I do with this stray dog?

There is this beautiful pitbull mix who is a homeless dog and still seems like a puppy and I need to know what do I do with a stray dog like this? Do I call the local animal shelter? Do I call the ASPCA? What do I do? Do I post the dog on Facebook marketplace and try to find a good home for her myself? Leave a comment and let me know what to do.