Okay it sounds like you are working for someone as an independent contractor ("....1099....") and will not receive a W-2, but more likely a 1099Misc or 1099NEC. So if you have expenses you have to enter them on a form called a Schedule C.
If you are so new at this that you do not understand, you need to learn fast. If you are not getting a W-2 that means that the "boss" is not withholding federal or state tax or Social Security or Medicare from your wages--and you will be paying all that yourself at tax time. If you are not receiving a W-2 you are not really an employee--you are an independent contractor. The IRS considers you to be self-employed.
https://ttlc.intuit.com/questions/2584365-am-i-an-employee-or-an-independent-contractor
https://ttlc.intuit.com/community/self-employed/help/what-is-the-self-employment-tax/00/25922
https://ttlc.intuit.com/questions/2902389-why-am-i-paying-self-employment-tax
https://ttlc.intuit.com/questions/2893577-does-a-1099-misc-mean-i-m-self-employed
https://ttlc.intuit.com/questions/2903027-how-do-i-report-income-from-self-employment
https://ttlc.intuit.com/questions/1901340-where-do-i-enter-schedule-c
https://ttlc.intuit.com/questions/3398950-what-self-employed-expenses-can-i-deduct
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
