@IMK Thanks for posting in our Q&A.
Based on my research, Microsoft Defender for Endpoint on Android needs Microsoft Defender for Endpoint Plan 1 or Microsoft Defender for Endpoint Plan 2. Please refer to the prerequisites in the following article:
https://learn.microsoft.com/en-us/microsoft-365/security/defender-endpoint/microsoft-defender-endpoint-android?view=o365-worldwide#how-to-install-microsoft-defender-for-endpoint-on-android
However, Microsoft 365 F3 license doesn't have Microsoft Defender for Endpoint Plan 1 or Microsoft Defender for Endpoint Plan 2.
So, it is suggested to contact your license seller to find a more cost-effective way to purchase licenses.
Thanks for your understanding.
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