You will have to wait until your employer issues the W-2.  Employers have until February 1, 2021 to give you the 2020 W-2.

The IRS will not be accepting any type of 2020 tax return until January 27, 2021 so there is no need to rush your tax return.  E-filing of the 2020 tax return will not be available until early January 2021.

The finalized IRS Form 1040 will not be available until January 7, 2021 (subject to change)

Please be careful about being in too much of a hurry to file your next tax return. Many tax forms are not available at the very beginning of the tax season, so you have to wait for your forms. The software still needs updates at the beginning of the tax season. 

Although the software will allow you to e-file in early January, the IRS does not begin to accept the e-files until almost the end of January.  So your return just sits on the server.  If you realize that you made a mistake or left something out—as many people do—you cannot change it.

Every year we see people who are in such a rush to file that they file incorrectly and incompletely.  If you file too early and leave out a W-2 or a 1099, or forget to enter information, you will end up having to amend your tax return---and that takes months.  Employers have until February1. 2021 to issue W-2's----and ALL of your 2020 W-2's have to be on the same tax return.  Many of the 1099's and 1098's you need do not arrive until late January or sometime in February.  If you are getting Earned Income Credit or Additional Child Tax Credit, the IRS is going to hold your refund until the end of February no matter how early you file.  There seems to be a greater chance of "early" returns being reviewed and those refunds are delayed, or early returns are more often subject to identity verification--which will also delay processing.  Filing too early may just be a recipe for a delayed refund.  It might go more smoothly for you if you wait until at least mid-February to file instead of e-filing during the first minute that you can do it.