Put in what you owe, the rate, and what you can pay each month. Then list your debts one by one and see whether paying the smallest balance first or the highest rate first gets you there sooner. The gap is usually smaller than people expect.
Paying $500 a month on $15,000 at 18.5%, you'd be debt-free in 3 years and 5 months and pay $5,291 in interest along the way.
Interest is added monthly at the rate you give, then your payment comes off. With separate debts, every debt gets its minimum and whatever is left over goes to one target debt; when that one is gone, its minimum rolls onto the next. No fees, no new spending, no rate changes. Nothing you type leaves this page.
Both orders get you out. The one that works is the one you keep doing.