Q: why i can't conecte to app store on my iPhone 6 on 4g but i can on wifi

if the 4g carrier block port 443 what you experience would happen read more about what ports are used for what

here

TCP and UDP ports used by Apple software products - Apple Support

Saeed13 wrote:

 

i can't connect app store on my iPhone 6 on 4g but no problem on wifi

Check your "cellular" settings and make sure you have enabled cellular data for the App Store app.