OneDrive should automatically sign you in when you log into your machine, you can check if you are signed in as there should be a 'blue cloud' in the task bar at the bottom right of your screen, if not you can open one drive by either selecting the OneDrive link on the start menu or via the pinned items on the right. I've added a screenshot below showing this:

Once your signed in you can open file explorer highlighted above and all of your OneDrive documents should be shown when selected on the left hand side of the file explorer as shown below.

Within this folder you can open, save and edit work as you normally do and anything within this folder will be automatically synced and saved online to be accessed anywhere :) 

If you have any problems at all, please let us know.

Kind Regards,
IT Support