Probably a stupid question but how can I do this?
This is the first time I use cloudflare so I have a lot to learn

What firewall do you use? Do you have an IP from cloudflare or a range of IPs?
I currently don't have a firewall (I thought that this was included with cloudflare) which one do u recommand?And I have an IP from cloudflare it I am correct.
(I have 2 nameservers from cf)