Boys I feel the pain I faced, my solution was below

I was using simple html ,js file to hit azure functions ( Localhost - VStudio)

I added

 "Host": {
   "LocalHttpPort": 7153, 
   "CORS": "http://127.0.0.1:5500" 
 }

this http one was my port on which my UI was running, this worked fine. Even "*" will work