Is a French PAC skydiving license equivalent to an AFF license?
If you mean you are learning to skydive and will be taking PAC instead of AFF, then the differences are minor. IIRC, in PAC the last jump is number 8, whereas in AFF and PFF it's jump 7.

There's also the Canadian version, PFF, and I assume other variations as well. Generally, schools do not follow any of these exactly and add their own variations.