I filed my federal electronically, right after that I received a w2. I need to make an amendment to 2019. The forms have not be availability from the IRS.

No..you cannot.

 

IF ACCEPTED: by the IRS:  You must wait for the original Refund...or pay the original balance due.

 

Then, the END of Feb...you start the special Amended tax return process  (not available right now anyhow), make all the changes needed (even a few more that you missed too..maybe) ...then print and mail the amended forms in yourself at the Post office.  Amended tax returns can take several months to process (and if you are in an income taxing state, you may need to amend ah one too.)

 

Next year, don't file until you have absolutely everything in-hand and ready...you'll save yourself tons of grief.

If you have filed your tax return and then discover that you have an additional W-2 to file you will have to wait until the IRS either accepts or rejects your tax return. 

  

If the return is rejected you will correct the error that caused the rejection, add the W-2 and refile your return.  

 

If the return was accepted by the IRS then you will have to file an amended tax return using Form 1040X to add the W-2 to your tax return.

 

This link to the TurboTax Help page  How to amend (change or correct) a return you already filed provides information on how to amend your tax return.  

@LeonardS 

 

Thanks, I missed the part about "maybe' the e-file would be rejected...if they are lucky it will be rejected, since that simplifies thing immensely.