Since there's no any option available to change the language in Google Drive, for changing the language on Google Drive desktop application, do following steps :
1. Open the Start Menu, type in the phrase "edit system environment variables" then choose the menu as shown below :
2. On System Properties dialog, choose Advanced tab, then click the Environment Variables... button. On Environment Variables dialog, create a new System Variable, named "LANG" and "en_US" on its value. Just follow the step-by-step as in the image below:
3. Turn off Google Drive desktop application, then restart it.
4. Should Google Drive desktop application menus are in English now.
|Google Drive's menu in English|
Try it yourself :-)