Get your taxes done using TurboTax

[Edited 03/29/2021 9:10 AM PDT]

The bonus you received is considered wage income ("earned" at your regular job), and is taxable in the same ways your normal pay is taxed. Your employer erred in reporting this on Form 1099-MISC - it should have been included in your W-2 and taxed accordingly.

There is a way to correct this, but you will have to enter the 1099-MISC in the "Income from 1099-NEC" interview in order to generate the correct forms (Form 8919). See the sample screenshots below for aid in navigating.

As @Opus17 correctly points out:

"There is a particular tax form for this situation, Form 8919.  When you enter the 1099-NEC, there should be a list of special circumstances and one of those says something like “Taxpayer's employer reported this extra money on a 1099-NEC but it should have been reported on a W-2".

This will trigger TurboTax to prepare a form 8919 using code H, which is designed for this purpose, which will collect the employee share 7.65% Medicare and Social Security tax instead of 15% self-employment tax.  

In fact, everything that your employer provides you as compensation for your services is supposed to be included on your W-2 and subject to regular income tax withholding and Social Security and Medicare tax, unless it falls into one of the excepted categories of fringe benefits, such as employer-provided health insurance.  

By paying you on a 1099-MISC, the employer is either, intentionally or from ignorance, trying to avoid paying their share of Social Security and Medicare, plus potentially unemployment insurance and any other items required by federal or state law."

@Opus17