Is fluorine reactive?
Yes, the most reactive nonmetal.
The reactivity trend on the periodic table increases as you approach Fluorine. Note that noble gases are not reactive at all, as they have their full completed octet of 8 electrons. Fluorine is the most reactive nonmetal, whereas Cesium and Francium is the most reactive metal. You can use these trends to compare reactivity, just make sure you filter out whether it's a nonmetal or metal.