Pages has a 20k-100k limit on static files, but if they just guide you to R2 to offload it, which is still Cloudflare.
Did you mean the CDN? In which case, I'm not seeing that in the terms. [0] Though, I would have expected they'd have a similar thing. R2 resources don't generally count towards your cache limits.
[0] https://www.cloudflare.com/service-specific-terms-applicatio...