So your parent implied borrowing and selling the stock immediately to "receive cash from your broker now" and by doing so they are required to return the stock

So your parent implied borrowing and selling the stock immediately to "receive cash from your broker now" and by doing so they are required to return the stock (unless the company goes bankrupt). In this way, you are both correct about what shorting a stock is. However, options are NOT like this. With options, the write side could receive a premium on their side of a contract for guaranteeing either to sell the shares at a specified price (a write-call) or guaranteeing to buy the shares at a specified price (a write-put). In either case, the person buying that contract can choose to either execute that contract or let it expire, meaning it could be the case that the writer (who receives a premium) may never have to act further (because the contract buyer never executes it, so the writer just pockets the full premium).