Can we please get some getting started docs?

Some basic info on:
1. how to control who can access CloudflareOS once its deployed,
2. how to enable gatekeepers,
3. how to customize the deployment
would be greatly appreciated!

Start by reviewing the repository’s existing documentation and the entry points for deployment, access control, gatekeepers, and customization. Document how users control access after deployment, enable gatekeepers, and customize a deployment, with clear examples or steps for each topic.

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