IS it possible for Admins to read CPUID of Tails users browsing their websites? Is there any difference between reading the CPUID of Intel chipsets and AMD chipsets? Is there any method to ensure this data is not being shared and being sent out from a Tails users PC?

None that know of.
No idea.
Yes: audit Tails, investigate, find ways to make this data leak remotely, report back, suggest fixes if needed.