Anyone can buy stocks in a margin account and then borrow against it as margin, and use that margin to make more money. If you can open a brokerage account, you can do this.
Shit can turn on you real fast though and you can lose a lot of money since you’re borrowing against the value of a fluctuating asset.
E.g $1000 stocks let’s you buy $400 on margin, but if that $1000 becomes worth less than $700 you gotta pay back that $400, but now you gotta sell at $700 or pony up more cash and that $400 you bought is also only worth $200, so you sell $200 of your $700 and suddenly you’ve lost 50% of the value
It costs money to buy a put contract to protect the loan.
So if you need a 1mil loan, now you also gotta buy puts that’ll protect a downturn of 1mil. So now you gotta sell stock which will be taxed. It’s less than 1mil so you’re taxed less, but you will have taxes.
Edit: you could zero cost collar (puts + covered calls) your investment to protect it’s current value, but you’ll give up potential gains as well to get the zero cost part. But this would be a way to protect the value without selling. If the options get exercised though, you’d then have some taxes to pay.