I have onedrive and my documents are sitting there. How do I access these documents from another computer?
Open any web browser and go here: https://onedrive.live.com
Your OneDrive is a component of your Microsoft account.
Your Microsoft account is a cloud account. A cloud account is a user account that is created on the internet, aka 'the cloud'. A Microsoft account is Microsoft's brand name for their version of a cloud account.
Therefore, your OneDrive is on the internet, and your documents are sitting there, on the internet.
Since your OneDrive is on the internet, you can reach it with any web browser from any device that can connect to the internet, anywhere in the world.