Can I change the lender of student loan? Can I start making payments while still in college?

You start paying your student loan when you're still in school. In fact, there are plenty of benefits of repaying student loans early. The first benefit of prepaying the student loan is that you'll be in a much better financial shape than others. Look at your loans and find out which one charges the highest interest rate. Make payments on that loan to get rid of it as soon as possible.

Have you taken out a federal student loan? Then only you can switch lenders if you consolidate your loans or apply for Public Student Loan Forgiveness or Total Disability Discharge. And yes, you can pay off the principal early by making pre-payments while studying. But make sure, your payments are applied to the principal, not the interest. And try to pay off the interest within the 6-month grace period.

You didn't mention the type of your student loan. Please come with more details to get the proper answer.