I have a question about the application online

<p>I hope there is someone who can answer for my question in next 3 hours.
I am trying to submit my application online by tonight. and It won't let me to submit.
when I apply online, the submit button is not even activated and I can't click it.
I filled all required parts on the page.
Do I have to pay the application fee when I submit the first part of the application?
Then, How can I pay it via paypal? does the applying page direct me to paypal or do I have to pay just using paypal?</p>