Your Office 365 account includes 1TB of personal online storage in OneDrive/OneDrive for Business. Files that you keep in OneDrive can be easily accessed from any web browser. Follow these steps:
1) Sign-in to your Office 365 account here: https://portal.office.com
2) Click the App Launcher button in the upper left corner and select OneDrive:
3) To create a new document or folder click New:
4) To upload files or folders from your computer click Upload. You can also drag files from your computer to one of your OneDrive folders: