SSH certificate authentication -> Document implementation steps

Hello,

Help is needed to create a walkthrough to implement a basic SSH
certificate authentication solution for when I access my VMs.

I want to make this solution as simple as possible, and shall include ;
-> deliverable is 1) either a .txt or .doc file plus 2) some chat for overall discussions
-> discuss cert issuance (use smallstep.com or not?)
-> describe VMs (Rocky Linux & Ubuntu) and clients (windows & Linux) setup steps
-> new user setup steps, including SSH client recommendation and setup, for Win & Linux
-> maintenance steps (e.g. cert renewals? cert expirations? add/remove users? add/remove VMs?)
-> assist me during implementation on my side

I will of course need you to test your steps before delivery of the document. I can provide you with two or three blank VMs if that is necessary or you can use your own environment for testing.

Some walktroughs I found:

https://www.sweharris.org/post/2016-10-30-ssh-certs/
https://smallstep.com/blog/use-ssh-certificates/

I just dont have the time right now to explore this by myself, thus the needed help.

Thank you
-F