Do i need a KMS key if all of my computers came with a windows pro licenses


I think it will be a simple question for you guys but it is necessary to ask you. because I tried my best but not solving a problem.

The computers that I manage all of the computers are HP EliteDesk with a valid license of windows 10 pro.

when I would like to do Sysprep i will after it I will reimage it.
-slmgr.vbs/ipk VK7JG-NPHTM-C97JM-9MPGT-3V66T (this is the generic product key)-slmgr.vbs/ato

although i am having the generic key. at the end I should active each on computer, the activation should look for the real key stored (i think) in the bios of the computer.

The question is I need to correct up Do I need to set up an ADBA/KMS server and purchase a KMS, key, Do I need any type of key to manage the activation, since they will be activated by the Sysprep process.

Thanks for your help