Step 1: Step 1: Login into portal.office365.com

Sign in with your Login ID and Password.

Continue…

Step 2: When entering account click on Admin as shown into the picture.

Step 3: In the Office 365 admin center, choose the Active users option.

Step 4: Click on the Three Dots in front of user as shown in the picture, and then click on the Delete User Option.

Step 5: Now a new window will appear, here some options are available regarding the user deletion, (from here we can assign the existing license to a new user if we want) click on the Delete option.

After clicking on the delete option we can see that our user is successfully deleted.