Hello there.
I've done a DevNet Snack Minute episode on using Atlantis as a Continuous Deployment tool within an SCM
https://www.youtube.com/watch?app=desktop&v=Kxr0RMKHoTI
I've also got a blog out on a similar topic
https://blogs.cisco.com/developer/automatingwithpullrequests01
The idea with this tool is that you connect the Atlantis build server to the SCM with webhooks. This build server has access to the infrastructure that you desire to automate (either via tunnel, VPN, or direct access).
Once you commit a change to a feature branch in a repo and initiate a pull-request (PR) -- the TF workflow will kickoff and you can manage the entire lifecycle of that change through the PR, and it will also include documentation of the work being done within the PR.
There are other methods and tools out there -- using the building of a bespoke CI/CD pipeline with GH actions, Gitlab-CI, Drone, etc -- but this is a batteries included approach.
Hope this helps!
q.