You might be able to find tax relief through what’s called an "offer in compromise." This lets you settle your back taxes with the IRS for less than you owe. According to the IRS, it may be an option if you absolutely can’t pay your tax debt or if doing so creates a financial hardship.
If you need more time to pay your tax bill, the IRS will probably give it to you in the form of a payment plan. A payment plan will allow you to pay back your overdue tax bill (plus accrued interest and fees) as installments over a period of time.