There is no way to "unsubmit" your tax return if you already submitted it. Submitting it is like putting a paper tax return into a mailbox. It's on it's way and there's no way to get it back.
You will have to first wait to see if your tax return is accepted or rejected. That probably won't happen until after February 12. If it's rejected you can add the missing W-2 when you correct the reason for the rejection, and resubmit it.
If your tax return is accepted, you will have to then wait until the IRS finishes processing it and you get your refund. Then you will have to file an amended return, Form 1040-X, to add the missing W-2. Here is a link to the instructions for filing an amended return.
How do I amend my 2020 TurboTax Online return?
thanks for the reply. I have a question how come when I click on the help button and click amend I dont see the amend 2020 yet but it said keep in mind that you have 3 years from the date you filed your return or 2 years after you paid the tax due to file an amended return which means u dont have to get it done by the April 15.
The thing is for 2020 I only filed for one of my job and thats the one I quit and recently got a new job and I need to file that one plus I need to file for robinhood too