When a bank gives you a loan of 300.000 euro's, they don't have to have 300.000 on their books... They can just create "virtual money" which they loan out to you. IIRC, the percentage is actually a little less than 10%. So, a bank can have 30.000 on it's books, and still give out a 300.000 loan AND get 279.000 in intrest. They don't double their money, they actually multiply their investment by a factor >9...
A very erroneous opinion. Or you are confusing it with another process.
Lending is a procedure when between a bank and a conditionally seller of a product or service, there is a buyer who does not have money. And the bank issues a loan, in a REAL amount of money (cash or non-cash, it doesn’t matter). Those. the seller, in return for his goods, receives real money from the bank. No other way. The seller does not need a promise to pay in the future!
But there is another process, when a bank can, for example, act as a "guarantor" of a certain "collateral". This is a completely different and more complex process, and there can really be “unsecured money”. But I repeat this again - a very specific process with which ordinary citizens do not intersect ...