Studying for technical interviews as an engineering major

I'm a rising sophomore at a top school that's almost completely focused in science and engineering; there are departments in economics, business, and finance, but my major is in Electrical Engineering and Computer Science, and I don't wish to switch out. I'm also considering finance as a career and hope to intern there after my junior year. How should I self-study the technical finance/business content? I can't take too many classes in these as my major workload is enough, but I'm really fast at picking up content and could probably read extra stuff in relevant subjects for IB. I'll be minoring in economics but technical interviews seem to be asking about stuff like accounting and corporate finance, not economics.