Additional information: Hii recently i had created a sub-doamin for my website to install phpbb but after the install i was going to admin panel then it showed site can’t reach why?? and when i tried to access normally same problem can you say me how to fix it? please
You can use subdomains with cloudflare, but not with our control panel integration.
If you sign up with Cloudflare directly, you can use subdomain, but you need to make sure you update the DNS for the subdomains yourself
point forum subdomain in cloudflare to right direction