How to know URL of a file in Google Drive?
1. Open the document
2. Copy the URL from the address bar.
Thanks. This ques was asked after doing the process listed by you. For eg., opening image does not display image-specific url in address bar
You're right, this does not work for JPEGs, and probably not for other images either. However, you can get the address (in Chrome, anyway) with just one more step. After you open the image, click on the blue "Open" button at the bottom of the page and then copy the URL from the address bar as mentioned earlier.
Right click on the file and select 'sharing'. Copy the 'link to share'. You can also change the sharing settings under 'who has access'.
Sharing settings overview
Direct Links And File Hosting On Google Drive
Best Method Public Folder