Issue with uploading xamarin forms ios app to app store?

Hi,

I am planning to upload my xamarin forms ios app to app store. I refer the following youtube video for that.

Steps telling in the video:
1 Login to your developer.apple.com and select Certificate Identifiers and Profiles.
2. Click Appids under Identifiers and click + button.
3. Give App Id Description and Explicit App Id(Bundle Identifier of the App)

I don't know what is the Bundle Identifier of the app. From where I can find the Bundle Identifier details in my xamarin forms app?
In the video, he is telling about the Bundle Identifier from 2:00 min.
Thanks in advance