$15000 is a lot of debt but if you work hard and pay towards that debt as much as you can then you should be able to pay off the $15,000.00 in debt within a few years.
If you can put even $250.00 per month towards the $15,000.00 of debt that would mean that you could pay off $3,000.00 of the $15,000.00 debt a year which isn't much but it helps some.
Although the more you can pay towards the debt per month the better off you'll be at getting the debt paid down before too much interest is charged and makes it even harder to pay back the debt.
You would pay off the $15,000.00 of debt in 5 years at $250.00 per month.
Even at $600.00 per month it will take 32 months to pay off the $15,000.00 in debt.
However interest can also add up over that time so you may not be able to pay all that back as new interest charges will be added in most cases.
So if you could pay more towards the debt if possible you could pay it off sooner.
If you have credit card debt then you should pay more than the minimum payment and ideally pay off what you borrowed on the credit card the next month in full.
This keeps interests from adding up and increasing your debt on the credit card.
Same with a loan, the longer you have a loan out the more interest that will be charged which makes it harder to pay off that loan.
Only borrow what you reasonably can afford and be able to pay back.