If you worked for the same company in 2018, you may be able to get the information from a Wage and Income Transcript from the IRS for 2018. Use this link to try: IRS Get Transcript
Or, if you have your last pay stub from your job, you can file your return by mail including Form 4852 as a substitute W-2.
The following TurboTax article will give you instructions: How do I file a substitute W-2 using Form 4852?
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