To add your profile photo to Microsoft 365 for business
Find a photo you want to use and store it on your computer, OneDrive, or other location you can get to. The photo needs to be smaller than 4 MB and can be a .png, jpg, or .gif file.
Sign in to Microsoft 365 with your work or school account at office.com.
Select the circle in the upper right hand corner of the page that shows your initials or an icon of a person.
In the My accounts pane, select the circle that shows your initials or an icon of a person. Change your photo in the pop-up that appears.