I have done the necessary coding for inApp purchase and i checked it in the sandbox environment and it is working well . but when i upload the project i don’t know how to attach the inApp that i added in the iTunes. After i uploaded my inApp status is same as before , it says “Ready to submit”. Below is the image of my inApp status that i used in my app.

can anyone please tell me how to solve this issue. Thanks in advance
If you Haven’t uploaded your app binary, there’s an option of adding In-App Purchases in the App Details in iTunes Connect. So your Product ID/Reference Name will appear in the In-App options of the App.
But
If you’ve already submitted your app, you cannot implement In-App Purchase in your released app. It has to be “attached” or added in a new binary and re-submitted.