It depends on what language you find most interesting to you or if you find them both interesting them you can learn both
French, more people are
It matters on which one is easier for you or which one you'd like to learn more.
Learning German has a reputation for being a challenging endeavor, but it doesn't have to be. Knowing how to speak English gives you a considerable leg up when learning to speak German. Afterall, German and English are considered linguistic siblings because they originate from the same mother tongue, both being Germanic languages.