If you use Chrome, you can launch Office Online programs directly from your desktop. The Chrome App Launcher sits in your task bar, like a Start button for programs you want to run in Chrome.
If you don't have the App Launcher yet, download and install it (in your Chrome browser, go to https://chrome.google.com/webstore/launcher). Then, in the launcher, search for Word Online, Excel Online, PowerPoint Online, or OneNote Online, and add it to Chrome.
When you're ready to use Office Online, click the program icon in the launcher.
Chrome takes you to the start screen for the online program. If you're not already signed in, you'll be prompted to do so.
Tip: You can add more Microsoft apps to the Chrome App Launcher. Try searching for OneDrive and Outlook.com.