If he is a W-2 employee he cannot deduct job-related expenses on a federal return.   Your state laws may be different.

https://ttlc.intuit.com/questions/4482873-which-federal-tax-deductions-have-been-suspended-by-tax-re...

No.  The tax reform plan of 2018 eliminated the miscellaneous itemized deduction for workplace expenses for W-2 employees, and raised the standard deduction for everyone instead.

(Prior to that the answer was "sometimes, depending on the circumstances, and depending on where you lived. But now the deduction is eliminated for everyone.)