If its the Federal Government that is issuing the Bonds... well, the Federal Reserve can actually just print the money out of nothing, into existence, by fiat, when they 'buy' some of the Bonds from the Federal Government, if other market actors don't want to pay for the Bonds with already existing money.

This is called the 'Primary Dealer Takedown' in fancy pants monetary/finance speak.

This more or less directly is monetary inflation.

But it can get very confusing, very fast, when you have some people arguing that the best way to define inflation is... actual price levels consumers pay, prices manufacturers/retailers pay for input materials, and others arguing that better definitions of inflation relate to the actual amount of dollars that exist, that exist in various kinds of accounts, etc.

Without going fully into trying to explain monetary theory and international Bond markets...

... this, and things like it, when the Federal Reserve just poofs money into existence, to exchange for... a Fed Gov Bond, or Mortgage Backed Securities, or what have you... this is where the 'money printing' most literally, directly happens.

And then the effects of that, well again, very contentious as to precisely how and to what extent, but this is where you get theories saying that money printing acts as an effective tax on the entire economy.

Basically those closest to the actual money printing suffer the least (or actually benefit), but those further away, down the line, they see price levels generally rise, to match the new number of total dollars in the system.