I'm excited that you are considering majoring/minoring in French. I absolutely love the French department here; the professors are incredibly engaging. I know some people that double major in science/engineering and a language; my friend is majoring in BME and Spanish. There are definitely more natural sciences and language majors, but it's definitely doable with BME. One of my favorite things about Hopkins is the lack of a core curriculum.You have to take a certain amount of credits of humanities and social science courses, they can be in whatever area you want. So, for me, most of humanities credits are French with a few other ones thrown in. For me, I chose to minor in French because I am more interested in conversation and french culture whereas the French major is more focused on writing eloquently and analyzing literature (there is also a french literature minor). I also wanted to take more classes outside of my major and my minor and I'm planning on graduating early, so that's the reason I decided on minoring in French. BTW, if you want to major in French Culture, you can actually do an interdisciplinary major in French Culture.
I know a bunch of science majors that have studied abroad in France. It's definitely much more difficult for engineering. For ChemBE, only a few study abroad (and that's people that come in with a LOT of credits). However, I've heard that BME is a little bit more flexible and you can either study abroad in an english-speaking country or save all your humanities for one semester and go abroad to a french speaking country. You have to make sure you start planning this your first semester though! However, if you don't have the opportunity to do this during the school year, there are a lot of options in the summer. We have a Vredenburg scholarship, which gives money to engineers who want to do research, an internship, or take courses abroad. You can literally go wherever you want if you get the scholarship.
To be honest, if you're more interested in molecular biology (and hard sciences), I would go for ChemBE. ChemBE is more science-based (from my experience) as we take 16 credits of advanced science (including Orgo, Biochem, Cell Biology, Biochem Lab, and an another class- you can take genetics). BME, from what I've seen, is a bit more computer based. My friend who is a BME does a lot of Matlab in his courses. I currently do research in an oncology lab in ChemBE. However, we have BMEs, bio majors, and even a pre-med East Asian Studies major. If you decide to major in BME, you can still work in a lab in ChemBE and vice versa. So, I would look at the courses online and see what interests you most.
So, we have three weeks of winter break. After that, we have three more weeks of winter break called Intersession. During Intersession, you can stay home for those extra three weeks, study abroad, or come back to Hopkins. At Hopkins, you can take up to three credits of classes. These classes are really cool; for example, they've had classes like the Science of Baking, the Psychology of Love, etc. They're really fun and interesting. Last year, I did research for credit (which was nice because I was able to work full-time instead of in between my classes and activities) and my freshman year, I took a history class and a writing seminars class. It was fun to take humanities classes.
Hope this didn't take you too long to read and let me know if you have any more questions.