Unlike with Microsoft Office 2016, with Office 365 you will get OneDrive along with the word, excel, powerpoint, and outlook. OneDrive is the cloud based storage program which is similar to Google DropBox.You can find OneDrive folder under C:/Users/UserName folder by installing the Office 365 as shown below.
OneDrive folder same as a regular folder, the only difference is whatever files you saved here will be available in the cloud so that you can access from anywhere through the internet. You can access OneDrive files from other PCs by installing Office 365 or through Office 365 Online portal.
To access OneDrive online, open https://login.microsoftonline.com/ and log in with Office 365 credentials (which were used while purchasing Office 365). Once login at the bottom of the page you can find “Open OneDrive” link as shown below.
Once you open the OneDrive, it displays all files which are available in the cloud as of now as shown below.
You can arrange the files as List, Tiles, or as Photo as shown below.