Hi,
In general, you could get started with the official documents released by Microsoft for each topics and investigate further by internet search on courses or videos. (List some the doc links for your reference)
Introduction to Hyper-V
https://video2.skills-academy.com/en-us/virtualization/hyper-v-on-windows/about/
Active Directory Domain Services
https://video2.skills-academy.com/en-us/windows-server/identity/ad-ds/active-directory-domain-services
Group Policy Overview
https://video2.skills-academy.com/en-us/previous-versions/windows/it-pro/windows-server-2012-r2-and-2012/hh831791(v=ws.11)
Or if would like to earn some certificates related these products, you could take a look at the MS exams.
https://video2.skills-academy.com/en-us/learn/certifications/browse/?resource_type=certification&products=windows
Hope this helps and please help to accept as Answer if the response is useful.
Thanks,
Jenny