Where should I invest my money monthly?

Okay so I'm a college student and every month I save up around 2-5k depending on the month. Is there a way to invest it. I have a meezan bank and I thought of opening a savings account or should I invest in index funds or stock market? If yes how do I get started. Main goal is to raise enough money for me to start a business in summers and keep on investing till I've completed my studies so that I have some money once I'm done.