that's because interest accrues on your principal balance, capitalization will cause more interest to accrue over time than if you had paid the interest. It will also increase your monthly payment on most payment plans
Yes, you can learn more about deferment and forbearance on our website.
another question for you regarding  IDR plan . What if I recently had a decrease in income?
In that case you can apply to have your current IDR plan recalculated. You don't have to wait until your annual recertification is due.