Hello Freeme!
I am sorry for your loss. If your spouse passed in 2023 you will file your tax return for 2023 as married filing jointly. Then the next year you will file as single, head of house hold, or qualifying widower if you have dependents and have not gotten remarried.
Here is a short survey on the IRS website about what your filing status should be https://www.irs.gov/help/ita/what-is-my-filing-status
This will help you determine if you should change your W4 to single or if you have any exemptions.
Here is more information on filing statuses: https://www.irs.gov/newsroom/theres-more-to-determining-filing-status-than-being-married-or-single
No matter how you file on your return, if you do not have any dependents then you should not take any exemptions on your W4 or you run the risk of not having enough tax taken out.
I hope this helps.
