How do you add whitelist?

I just got new computer about 2 weeks ago. It came with windows 10 its fast and I like it for most part. One of my favorite sites for Runescape is http://runescape.salmoneus.net/ I keep getting error message 522. I have checked many times on different sites to check if a website is up and down and people I know say it is up.  It is carried by CloudFlare and I contacted them they said to check to see that my host has their white list added. Who is my host?  I checked with our Charter.net, our IPS they had no clue they said they don't block sites.  I don't know what else to do unless I am supposed to add to Norton Security.  I don't know how to.  Can someone please explain?  Thank you for any assistance.