Find your picture icon on the top right of any of the Microsoft Applications you should be able to go to your Microsoft 365 Account Settings.
The easiest way we have found to change out the picture is in Microsoft Teams:
When logged into the Teams program on my computer, Click the circle picture icon on the top right. Then click on the photo itself and it will give you the option to upload a new one, or delete it:
If you are in other Microsoft Products, like Word, you can go to your Account Settings by clicking on the same picture icon. Clicking the "View Account" link should get you to your account settings on the Microsoft Office Online website:
Selecting "Personal Info" gets you to a place where you can choose to change your photo:
You can upload a new photo, or clicking the little X should remove the photo then you save it.
