When you add additional Apps to the Chrome Browser, you may (and may not) find them under the red New button in your drive. So where you create a new doc, go to the bottom and choose more and you may see them there (after a refresh and sometimes relog) to use. Or, when you add a new tab in the Chrome browser, you can click on the colorful Apps Launcher on the upper left and your added apps from the Crome Store will be a choice on the new page. You may need to refresh to see newly added ones. You can grab and move those how you want. Notice the arrows to show you may have more than one page of Apps.
Extensions will be an icon to the right of your Chrome OmniBar in the upper right hand corner.
Add-Ons will be attached/embedded in Docs and Sheets and Add-Ons is a choice to see in the menu items. They do not all go into your Apps-Launcher unless you choose to do so.
Instructional Technology Teacher