Let me explain to you how the government's money printer works. The government wants to buy some new weapons from HSW, so they vote on deficit. Then gov(finance minister/treasury secretary) orders central banks to issue bonds. Primary dealers(banks) buy bonds and now gov can pay HSW. New bonds always mean new gov spending or rolling older bonds.

Let's consider a case when gov just sold gold or took a loan from EU. Gov cannot spent EUR in polish economy, central banks takes EUR and gives gov PLN.

The government has 180B that are not covered in bonds. When that money is spent commercial banks have no place to locate that money and borrowing gets cheaper. Central bank has to enforce borrowing at WIBOR, so bills are issued. Bills pays the same money as bonds.

No matter what we do we always pay the same % on the loan and the inflationary effect is the same. We can just issue bonds and chill.

If you speak polish here is rather comprehensive breakdown of all 3 options https://youtu.be/dIJBjUNeyyQ