Regular W-2 employees are no longer (since 2018) allowed to deduct job expenses, including the home office deduction. If you're self employed, you can deduct the cost, as a business expense, on schedule C.
Even in the "old days" , job expenses were only a misc. itemized deduction. You only got to deduct that portion of your misc. itemized deductions that exceeded 2% of your AGI, and then only if your total itemized deductions exceeded the standard deduction (which was doubled under the 2018 tax law. . (2% rule explained: https://ttlc.intuit.com/questions/2902781-what-is-the-2-rule ).
