Here are some links to help you:

On a browser: 
https://help.dudesolutions.com/Content/FAQ/Creating%20a%20Bookmark%20or%20Desktop%20Shortcut.htm


On an iPad / iPhone: 
https://www.support.com/how-to/how-to-add-a-bookmark-on-iphone-ipad-or-ipod-touch-12470


On an Android: 
https://www.support.com/how-to/how-to-add-a-bookmark-to-an-android-phone-or-tablet-12468