Borrowing from the National Bank: how does it work?

A national bank would not be a bank if it could not lend money. Indeed, only a commercial bank can take out a loan from the national bank, but other than that, the process is not that much different from when you as an individual take out a loan from a commercial bank. To take out a loan from a national bank, you would also need collateral, independent third parties and - as for all financial institutions - risks are controlled to a maximum.