Hi everyone,
I need help! I have already submitted my Cornell ED application, and there are just so many things wrong with my application. I submitted it way to soon and I should have spent a lot more time on it. I got too excited! 
On my application portal, there is a form to submit that withdraws my application. If I withdraw my application, will I be able to send in a new application this year? I do realize that I may have to pay the application fee again, ugh.
No, you will not be able to submit your application again, as I don’t think the Common App does not sync backwards from application portals, and doesn’t know that you’ve withdrawn your application (for example, I applied ED to one school last year and decided to ED elsewhere, and even though the first college updated my decision round, the Common App did not and I had to submit a pdf ED agreement to the second school.) IIRC you are not supposed to submit an application using multiple application systems (Common App, Coalition App etc.)
I believe withdrawing your application means that you are not interested in pursuing admission further to Cornell this year (for example, if you were admitted ED elsewhere and were required to withdraw all other applications,) and would have to apply again next year if still interested. If there are major errors, you can try contacting the admissions office by email and provide them with the updated information, although there’s no guarantee that they will take into account edits (barring contact information, course schedule changes etc.)
Hope that helps! Good luck with admissions!
Why don’t you see if you can make your corrections/additions and then resubmit? Usually there is a place to add new information also. You can also contact your Cornell admissions person for your school.