Internships are definitely important for iBanking jobs. Usually you want to have an investment banking internship after sophomore and junior years of college. Banks come onto college campuses to recruit for internships in the late fall or mid-winter. When you get to college, ask your on-campus career office what the timing was like last year, to get an idea of what the timing will be like this year. You should look at some of the job placements from last year to get an idea of what is required. Usually those requirements are: high GPA, previous work experience of some kind (e.g., other internships), and a proven interest in finance (e.g., a club or two). Once you get an interview, you'll need to practice a lot for the interviews (they're usually very challenging), but that's getting onto a different question.
Product Specialist at Google
Mountain View, California
To add to the answer above, reach out to upperclassmen who have had internships at the companies you are interested in. Schedule an informational interview to talk about their experience, firm culture, leadership, and - most importantly - how to get the job. Upperclassmen are also the ones who return to campus and select who is interviewed for an internship or full time position, so these relationships are not to be undervalued.
Also make yourself and your interest in the firm known - attend the informational sessions, participate in any on-campus events or competitions the firms have, apply for an externship (or shadowing full time employees there for a day or two), look for opportunities to connect with these firms as much as possible. At the end of the day, if you are just submitting a resume that looks the same as everyone else's and no one in the room knows and can represent you, you are less likely to get an interview.
Bengaluru, Karnataka, India
Yes, internships matter a lot for a career in Investment banking. You should start looking for an internship in your 2nd year of study so that you have something concrete in the final year. Also, various top rated firms, Goldman Sachs, JP morgan offer internships. You can check on their comany pages.
Business Analyst Intern at LinkedIn
Yes, most people who do investment banking full-time right after college are people who had experience in investment banking or at least some sort of finance role as an intern. To get an internship at a bulge bracket or even middle market investment bank you probably need to have a high GPA and maybe have done a few case competitions that focus on investment banking. Also, being able to network well and have a lot of contacts in the finance world would help greatly. A lot of my college classmates have gone through interviews with investment banks, and they mostly tell me that it is extremely competitive, especially at the bulge brackets. The interview process is usually a 1st round, maybe a 2nd round, followed by a superday (a full day of interviewing with analysts, to VPs). It is mainly a behavioral interview with questions like why IB, or why this firm, and then some technical questions thrown in like walk me through a DCF etc. But, moving back more towards your questions, if you are just about to start college try joining a few business clubs or join a professional frat and try getting some work experience.
I hope this helped and I wish you the best on your future endeavors!
Vice President at Barclays Capital
Brewster, New York
One important aspect to note is that the timing of internships for undergrads is usually the summer between their junior and senior years. If you miss that timing it becomes more challenging to find a full time IBD job after graduation because most of those positions go to interns from the previous summer that received offers at the end of their internship. Timing is important here so talk to your career services offices and may sure you have a clear idea of what deadlines exist for applications, interviews etc. Good luck!