Have a clear picture of what role you want in the end. Is there a specific company you want to work for? A specific technology you want to use?

To talk about my career, instead of going into CS, I ended up going into engineering, but after working I technically? ended up doing CS simply because I did coding on the side throughout uni. During my first year working after grad, after I saw what the industry is like, I painted an idea of what I want to do, got back in touch and talked to a bunch of my professors, and specialized in a CS-adjacent (technically it is CS according to my country, but I don't agree) field, which is where I am at currently.

So when you say you want to study data science it sounds very general. There are RA jobs in universities, planning roles in manufacturing/O&G plants, forecasting for businesses, bog standard accountant roles, engineering R&D, and that's just off the top of my head for data science, but your CS knowledge would offer you an even wider gamut of roles to choose from - though employers look for specializations first and foremost. Have a look around online regarding what roles you can get, research those in depth, and if the vibes are vibing then you can work towards that in uni, choose electives and major courses you want that interest you. Don't be afraid to refine your trajectory during your studies, especially since you'll get to know some faculty that can guide you as you learn about what's possible. If you specialize you will not have any issue at all getting a job with such a degree, and the fact that you vibe with whatever you specialized in will help you a lot.