Banks make money by A. charging interest.

B. charging the Fed.
C. selling customer assets.
D. time-share programs.

The banks lend money to customers at a higher rate than they pay to depositors or than they borrow it.
The difference, known as the margin or turn, is kept by the bank.
For example, if a bank pays 1% interest on deposits, they may charge 6% interest on loans.
More specifically, banks collect interest on loans and interest payments from the debt securities they own, and pay interest on deposits, CDs, and short-term borrowings.
this is through charging interest rate.