Reverse proxies - How do I conclude traffic originating from a reverse proxy is legitimate?

Alright - so i am a fresh infosec graduate who has marginal experience in the web exploitation side of things, and i have no real hands on experiences with “proxies”.

My client has alerting on traffic originating from a badlist of geolocations and one of the detected ips is a Cloudflare reverse proxy.

I have so many questions…

1. How do i check if my client has a reverse proxy configured? “How do i spot a reverse proxy which is …

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