OneDrive seems to be built into Windows 10 as far as I'm aware, but you must configure it to do much of anything. There was a proper OneDrive application at one time, but I don't know how much of a thing it has been since Windows 8 (10 it just seems part of Windows Explorer plus some hooks in 10 proper). It doesn't show as a tile for me on either my personal or work machine, but that might not be the case for everyone. If I click on it in the applications list on the left, it opens Windows Explorer to the OneDrive "folder".
Office 365 that is interesting because on a clean install, I still had to go to office.com to install it. I didn't have icons for Word, Excel, Powerpoint, etc. and certainly not the GBs of data already consumed by it. I'm looking at my work machine at the moment and it has an "Office" tile that I can sign in and use the web versions, but it doesn't appear to be a full Office install.
Office 365 that is interesting because on a clean install, I still had to go to office.com to install it. I didn't have icons for Word, Excel, Powerpoint, etc. and certainly not the GBs of data already consumed by it. I'm looking at my work machine at the moment and it has an "Office" tile that I can sign in and use the web versions, but it doesn't appear to be a full Office install.