You have to remove them, otherwise you cant use Cloudflare. Please read support.cloudflare.com
No, unless your host forces you to use their nameservers, you wont lose anything. Of course, you need to make sure the DNS records on Cloudflare match your host.
They do match. As I’ve said, I replaced the jellyhops with the cloudflare ones. Okay, I removed the ns1 and ns2.vior.pl, I pressed recheck and now I guess I’ll wait.
Okay I got the email now. What if I want to add a subdomain? For example http://sfgame.best loads perfectly, but my subdomain I had (http://w1.sfgame.best) doesn’t.