You do not have to borrow a large sum to qualify as a borrower. For example, when you have a credit card, you are a borrower. The credit card company is loaning you the money to pay for your purchases. Also, when you get a mortgage to buy a home or even a home equity loan to make a home improvement, you are considered a borrower.
In order to borrow funds, you have to apply for a loan. Your approval for the loan is contingent on your ability to repay the debt and also your past history of repaying loans. In order to determine this information, the lender has to find out certain financial information about you including your income and assets. Also, the lender needs to see your credit report in order to know your history of repaying your debts. A credit report is compiled by a credit bureau, which uses your personal information, credit history and public record to create the credit report. It is then summed up with a credit score, which is a three digit number. Usually, the higher the number, the better.
Assuming everything is in good standing, the lender makes a loan based on how much you are asking for and your ability to make the payments.
Since you most likely will be a borrower throughout your life, it is important to faithfully repay any loans so that you have good credit history. It is also important not to borrow too much so as not to overload yourself with debt.