If you need to or want to switch between a work or school account, it's fairly simple to do so. And you don't even need to leave the Office apps you are using. To do so, simply select your name or initials in the top right corner. Then choose Sign in with a different account and follow the steps. If you had already previously added another account, it should display after selecting your picture or initials in the top right corner. From there, you can select the other account you want to switch to.