So just got back to this... so if it is parked on the bun you need to change the nameservers at cloudflare to actually get the domain to work. Without that step cloudflare can't do much with it. Cloudflare will tell you your own personal cloudflare nameservers, porkbun will have set them to theirs, so firstly find out what the nameservers are set to in cloudflare. Work through this guide

https://developers.cloudflare.com/dns/zone-setups/full-setup/setup/

Once cloudflare has the nameservers and they are resolving, which can take 24 hours, you can then route through your tunnel or whatever...