I worked for DoorDash. I know how much I made. Can I file without a 1099 form?

By all means wait for the form which may contain additional information. If you have to amend your return later it will be a big headache. 

You can enter the income without the 1099NEC.  As long as you report the same amount or more.  And you know you need to enter the gross income?   Not just what you made after expenses.  You enter expenses separately.

I would just enter it as Other self employment income or as Cash or General income.  You don't need to get a 1099NEC or 1099Misc or 1099K.  Even if you did you can enter all your income as Cash.  Only the total goes to schedule C.

How to enter income from Self Employment

https://ttlc.intuit.com/community/self-employed/help/how-do-i-report-income-from-self-employment/00/26653

If you know how much you made you can just enter it now as long as you report all of the income and have an accurate number.

I am in the same situation.  I am having trouble accessing my 2021 Doordash 1099.  I know exactly how much I made, I know the company’s address, and I know their EIN.  My only question is, in CA we are paid an additional earnings adjustment due to prop 22 if we don’t earn the guaranteed amount for time worked/miles driven.  

I plan on reporting additional earnings from prop 22 as taxable income.  This would be the correct way to do it right?

thanks-

You must report at least as much as what is reported on the 1099 form the IRS gets.   If you report less then expect an IRS audit.  So I would try very hard to access the form before filing to be certain.