I think that you're chasing something that might be less than realistic (in a way common to new graduates): an extremely rewarding and fulfilling work experience at entry-level. I'm not saying that that's an unreasonable thing to want, or that work will just be an extension of what your internship has been like. But this stuck out to me:
I understand that interns aren’t usually given interesting work but I thought I would gain some valuable experience.
You are gaining valuable experience, insofar as doing your assigned work without being stimulated or entertained is something that will almost certainly come up in your career (more or less often, depending on your field, level of skill, etc.). Sitting at a computer screen for hours on end describes an awful lot of jobs these days, if imprecisely. Experience working for an impressive firm can be valuable on a CV, as can be working overseas.
Your current situation is that you find your assigned work trivial and your supervision light, which means that you have a lot of paid free time you can apply. That you are in such a situation but can't find something to do with that paid free time suggests that you might have a personal issue to address rather than an external one. You could even use the time to make yourself more attractive as an employee and seek out better opportunities, as suggested by Victor. At a minimum, do that rather than saddling yourself with even lower income and a gap on your CV, just to pursue the same end without any additional benefits.
Your boss has said that this situation will change in a matter of weeks, so it might be worth sticking it out until then. The option to quit will always be available. Your question
Is it okay to leave the internship if I feel as though it’s not going anywhere
is too subjective to give a good, clear answer to. But I suggest considering it from this angle: what would the next thing you do be? If you have a more attractive job (internship or not) lined up, then leaving while things are slow might be very attractive and understandable. You want the better opportunity, so you move to it. If you do not have something else lined up, then your rationale is essentially that you can't be bothered to do work you feel is dull or not providing the stepping stone you want for yourself (never mind any interests the company might have). That can also be understandable, but it's a worse look when someone is reviewing your job application.
Moving towards something better is a much better look than moving away from something you think you're too good for.