Cloudflare counts Neurons, its own unit of compute, instead of requests or tokens. The same 10,000 Neurons therefore buy a different number of requests on each model: look up the model on the pricing page before estimating your daily volume.
The allowance resets at 00:00 UTC. Using more than 10,000 Neurons a day requires the Workers Paid plan, where the excess is billed at $0.011 per 1,000 Neurons.