CI/CD pipeline for networking - What does it look like?

Note, I've posted this in a Slack group but posting in a couple of places to get different opinions. Sorry if you've seen this already.

I'm working with someone to develop a NetGitOps (whatever that means) based management environment in a lab. I have some questions about what it looks like. We're thinking of using Github, Ansible, and Drone.io, plus a few tools for testing but we're not there yet. Here are my questions.

The way we are picturing this is we'll be developing an Ansible playbook which houses configuration components, such as SNMP settings, NTP, and the like. Configuration components will become more complex but for now, we're starting there.

​

1. Within Ansible, what would my structure be and how is inventory managed? Would I have everything defined as variables and then roles which generate a configuration snippet based on the platform?
2. How does Drone know which devices require configuration changes to be pushed, probably via Ansible, to which devices? It shouldn't push configurations to devices which aren't updated.
3. How do we onboard new devices when they're added? Is it using zero-touch provisioning methods, such as Ansible Tower? This is step 5 in our process but I'd like to have it roadmapped.