Can you explain that to me like I’m an 8 year old?
I think a key point is to realize the government has given the Federal Reserve by law an ability reserved for God in the Old Testament. The new money is not printed, but spoken into existence in exactly the same manner as God created the heavens and the earth in Genesis. However unlike Gods creation, money has no substance at any time. In spite of that people do exchange items of real value such as labor, cars, and food for words spoken over a phone by a twenty something Fed bond trader. This person calls a company such as Goldman Sachs that has an inventory of securities it brokers for the Treasury Department, and pays lets say $1 billion for securities. Until the trader speaks $1billion, the money to pay for the notes or bonds does not exist. Anyone else purchasing the bonds does so with dollars already in circulation.
Now if the Fed and the Treasury get rid the bonds they own and owe, the Fed does not have anything to offer in the marketplace in exchange for the money it created. This means the new money is on its own and continues to exist even if people have doubts about that full faith and credit statement appearing on the Federal Reserve notes we carry in our wallets. If they existed the Fed could sell bonds and reverse the process I described in the previous paragraph. By reversing the process, the Fed reduces the money supply and reduces inflationary pressures.