My site migrated to Netlify Create App from stackbit , missing models

please help me solve this issue, I can’t edit the site and add new content

Which site are you referring to?

The sire was written with stackbit yaml, is there an auto converter to migrate to the new format?

As discussed with the devs, this appears to be a case of an extremely old project. You should simply create a new site with a new config instead of migrating or upgrading in any way.