The only Biblical holidays are the Jewish holidays, which were uttered from the very Mouth of G-d and may be found in the Divinely-dictated Torah.
Where would I find Hanukkah and Purim in the "Divinely-dictated Torah"?
ZC, careful with your “Divinely-dictated Torah”
No Jew claims all the Torah was divinely dictated — you are veering into Muslim territory there as the Mohammadens claim the Qur’an to be divinely dictated and uncreated.