Get a credit card; and a new savings account. Put an amount of money equivalent to the credit card's credit limit in the savings account. Don't touch that account so long as you have the credit card. Set up autopay for the full amount on your credit card every month.

And there you go… you have a credit card with all the benefits associated with that; but you're completely safe and don't run the risk of going into debt. If you're spending too fast, or if things go wrong, you can immediately close the credit card and pay it off in full with the amount in the savings account.