@Nadeem Akhtar Mohmand, Thanks for posting in Q&A.
For Microsoft Intune app, it is used for Android Enterprise enrollment. This app will be automatically installed during the device enrollment process. For example, Android Enterprise fully managed scenarios.
https://learn.microsoft.com/en-us/mem/intune/apps/apps-add-android-for-work
For windows device, we use company portal app which mentioned by Jordan. And BYOD enrollment method needs to download company portal to enroll the device.
In General, there are many enrollments for windows, you can choose the one suitable for your situation if you want to do the enrollment. Here is a link with more details for your reference:
https://learn.microsoft.com/en-us/mem/intune/enrollment/windows-enrollment-methods
Hope the above information can help.
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