You can always file for unemployment but that doesn't mean you'll get it.
They take everything into consideration especially the income that you're still making. Once you reach a limit, you're not getting anything.
For instance, if you lost your main source of income but you still own a rental property and you're making $3K a month. You will not get unemployment.
Also, if you were fired from a company and the company choose to fight your claim and said it was through your own fault you were dismissed, you will not get unemployment.
Unemployment benefit is just enough to get you food and basic necessities. It's not meant to help supplement your BMW car payment.