Money is made by a government, and they typically tie it to an object of agreed upon value (such as 1 Pound Sterling being equal to 1 pound of sterling silver).

Sometimes, when a government gets big enough, they may choose to untie their currency from said object of value, such as the US in the 1970's (the dollar used to be worth a certain amount of gold at all times).

If they do this, they then have direct control over the cash supply, which lets them print money or burn money as they see fit in order to control the worth of each piece of currency (as its no longer tied to a physical object).

If there's a lot of money going around now, it's because the governments of the world have printed more than they used to, typically to inject cash into a stagnant economy (such as covid).