Patching for VMware Infra VMs

Dear team,

montly basis we are patching all VMs except VMware infra VMs, now we r planning to patch VMware Infra VMs also.I have below list of VMware infra VMs, just want to know which VMs we have to taget first (means install Windows Update restart then target 2nd VM, then target 3rd VM and so on....) need ur help so that we will

AD

ADC

vCenter

SSO

Inventory

UpdateManager

P2V-server

Do I take snapshot or clone as a backup.

Note: we have 1000 of server where we do monthly patching activity (as a Best practice we test the same in dev/uat environment then deploying the same in production environment).

regards

Mr VMware