I completed my taxes yesterday for the job im currently working at. Unexpectedly i recieved my w2 from my last job from january 2020-march 2020. How do i add the w2 i recived today to the w2 i complet

[gloriah5200]

Yes, all income received during the year is to be included in one tax return for you for the entire year.

Since you already filed your return with the one W2 you worked in 2020, but omitted the other one, then you will have to wait until IRS accepts or rejects the tax return filed.  If IRS accepts it, then you will need to file an Amended Individual Income Tax return (Form 1040X) to include the additional W2 to your annual income tax return filed.  If they reject your return, then you can refile the return including the newly received W2. 

For additional information on filing an Amended Income Tax Return