When you purchase Windows Server 2022 Standard or Datacenter in 2 Core license packs, you will indeed receive an activation key. This key is provided regardless of whether you buy a single 16 Core license or multiple 2 Core licenses to meet the minimum requirement of 16 cores per physical server.
So, if you buy 8 packs of 2 Core licenses, you will receive an activation key just as you would if you purchased a single 16 Core license. The key you receive will be used to activate the server, ensuring it meets the licensing requirements.