New Pitbull that wont eat and throws up when she drinks; Help please.

Hello I just join this forum after getting our pit bull Genna from the pound. She is an incredibly happy dog. We don't know how old she is or any of her history; she was a stray. I can't get her to eat anything. When she drinks she ends up throwing it all up, on walks she will eat a bit of grass and then throw it up. I know she is new to our house and nervous, but i worry about her not eating. To see if she just didn't like the dog food we bought, we put just a wee bit of bacon grease on her food and she still won’t eat it. Who doesn't eat bacon? Do ya'll have any suggestions or advice that might help her?

Thank ya’ll so much.