https://www.khanacademy.org/economics-finance-domain/core-fi...

It would be useful for you to explain how 'making loans of deposits' is not a reasonable simplification of that.

Of course actual banking practice is more complicated, but the core meaning of fractional reserve banking is to make loans (or investments, but that is a reasonable thing to leave out in a simplification) out of (demand) deposits (the difference between a deposit and a demand deposit is just a technical matter, for btc the lending institution and depositor would have to work out how immediately available the deposited coins would have to be).