afaik, there’s no way “convert” a running system into a playbook. I’d recommend looking at what your systems have in common (installed packages, timezone etc…) and create playbooks based on that and work your way up from there.

I’ve been using Zen and Librewolf, I recommend both of them but Librewolf will give you the privacy out of the box. A friend of mine uses Floorp and he seems happy with it.