Thank you for asking this question on the **Microsoft Q&A Platform. **
Even if is a BYOD, this device must be enrolled in Intune as a personal owned device
Source: https://learn.microsoft.com/en-us/mem/intune/enrollment/windows-enrollment-methods
Then you can get the Company Portal:
Source: https://learn.microsoft.com/en-us/mem/intune/user-help/enroll-windows-10-device
Hope this helps!
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