Writing traefik.toml file. Need to learn?

What is preriquisite to learn traefik? I know nginx, docker, k8s basics. nginx in full flow.What else should I learn before learning traefik?

Please use yaml, not toml.

Why "learn" Traefik, what do you want to achieve?

I want to use X-Real-IP as in nginx (X-Forwarded-For) in traefik.

Both headers are automatically set in Traefik for the proxies/forwarded request.

If you want to use them inside Traefik, you need to trust them (doc).