I don’t have change for a thousand yen bill.
This is a game in which you scoop thousand yen bills with a paper scoop from a water tank.
"Are you burning a thousand dollar bill?" "No, it’s just a thousand yen bill."
You know what 千円 is (1000 yen). So if you add a bill to that you get a thousand yen bill. That's just the little rectangular piece of money that is worth 1000 yen.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.