You have to ask yourself what you're aiming for. What you want. And then formulate an attack plan. Sorry, but you're not going to be able to get a finance internship and a research internship and a coding internship at the same time, while also becoming a writer. Mastery takes 10,000 hours of deliberate practice (practicing, and then immediately implementing conscious corrections based on masters' recommendations regarding the technique).
What do you want... Social status? Peer recognition? Parental recognition? Access to high-quality sexual partners? Money to buy toys? Happiness?
Carefully evaluate if you are working on any of the above things as means to an end, or ends in themselves. If you aren't, it's OK: just try to figure it out what it is you really want, so you can attack it directly. Spend time investing in understanding your emotions, and it will pay dividends later.
If you really really just want to do math physics chemistry biology economics politics history computers etc., you can. You just have to focus on improving your skill levels in each domain in order to create a meaningful impact. e.g. Improve your social intelligence in order to understand how to build something people want (figure out why people like talking about sports and dating and parties and clubs and stuff...hint: it happens for a reason, try to be open-minded and understand that everyone is human); improve your coding skills in order to understand how to actually make it. Read history books. Take advantage of all your free time in college to do more reading. Optimize your sleep schedule to use polyphasic sleep and spend all your time reading and working if that is TRULY what you care about. That is one good attack plan if you analyze your emotions and find out what is really important to you. But my guess is that it isn't.
My guess is that you just want to fit in and seem recognized as a contributing human being. Who doesn't?