In Acts 15 there is the letter that they wrote to the gentiles about this and what they thought. In Acts 15:1 some didn't think they were saved and in Acts 15:11 Peter said how he thought they both were saved https://www.biblegateway.com/passage/?search=Acts+15&version=KJV . Were the gentiles under the covenant made in https://www.biblegateway.com/passage/?search=Genesis+9&version=NIV when the Apostles met in Acts 15?
You are talking about the Noah covenant? Wow, no one ever gone that far back to a time when all were Gentiles. There were no Jews nor Israel in Genesis 9.
Was that a mistype?