This assumes electronic funds and no need to keep physical cash on hand.
It requires that depositors can only remove a certain amount of physical cash at any given time based on whatever the minimum holding requirements are for the bank.
It explains why there is a drive to go to all digital currency...no physical reserves required at all at that point.
Given this scenario anyone should be able to become a banker overnight. The only requirements would be 1) an appropriate accounting system to track debits/credits and 2) someone to take the first loan.
It doesn’t require electronic funds, the same process was done with ledger entries and very large denomination currency in the pre-computer era. Digital processing just speeds it all up.
Commercial banks do have reserve requirements, funds that they have to leave on deposit at the Fed. They have to come up with starting capital, their loans can only be a certain multiple of their reserves, they get audited by a number of gov’t agencies.
“Given this scenario anyone should be able to become a banker overnight. “
There was an era of “wildcat banking” in the 1800s where something like that occurred. Banks could issue their own currency back then. Bank currencies fluctuated against each other and gold like foreign currency trading does today.