Cloudflare - Name servers Changing proplem

Hey all, so i tried to protect my site with Cloudflare today and then it required me to change my name servers to Cloudflare’s nameservers so is it allowed and how to change it on the Control panel ??? (if allowed)
Current Nameservers Change Nameservers to: Remove this nameserver Remove this nameserver Remove this nameserver

please some help

If you’re using your own domain name registered elsewhere, you can change the nameservers of your domain on the site you registered it. You cannot change the nameservers of a free subdomain.