Office 365's robust email spam filtering system gets it clout from both work and home email systems; it is learning how to identify spam from a multitude of email and so it is quite reliable in this regard.
If a safe email does end up scoring as spam, you can add the email address to your safe senders list.
If you're familiar with Hotmail or Outlook.com, it is a similar process.
1. Log into your Office 365 email account.
2. If not open by default, go to your Mail app.
3. At the top right, click on your configuration wheel, and select 'Options'.
4. You will see a box where you can enter an email address, and also check a box to trust any email from people in your contact list.