Hello there,
If you have selected EWS category in your application form, then you need to provide the necessary documents. If you cannot provide then your application may stand cancel. You just can't say the authorities about your income, they need documents as a proof. Hence it's important for you to get an EWS certificate as soon as possible so as to save your application from cancellation.

But the authorities don't cancel the application easily. If your application is not cancelled, also you can't provide any category certificate, then you will be treated as a general category candidate and your CRL rank will be considered for getting admission in the college.

Hope this information helps you.
Good luck!!