I have always seen the word “believe” to just mean you are convinced of something, or at least for some reason you think it is more likely than not. How much that belief relies on faith or evidence will vary based on the subject.

If I tell somebody I “believe in” science, it’s because I have spent decades observing the results of actually measuring and studying the world around us. It’s kind of a philosophical statement and not a factual one though, because the “belief” is that it’s the best way forward.

I also don’t think the word “believe” suggests certainty, because when it comes down to it I don’t think I am really 100% confident in anything. Not that it makes a practical difference in real life.