Go to settings and find an option named as Reset and Backup. It must be towards the end of the settings menu. Open it and select an account you wish to take backup on. Then turn on the backup. Your device will be backed up on that account.
: Download App Lock from the Google Play Store. When you first start the app, you will be prompted to set up an unlock pattern for which you need to provide an email ID for security and backup purposes.
: You will then be taken to the main screen of the app. Under the Privacy tab, scroll down to find a list of applications that you can lock. Tap on the app name that you want to lock. The first time you lock an app, you will be prompted to grant App Lock Usage data access.
: Press the back button to go back to the main menu of App Lock. Now, you can lock any app that you want by simply tapping on the lock icon near its name. At this point, if you try and open any locked application, App Lock will prompt you to enter the unlock pattern that you first created. To make the app use the fingerprint scanner for verification purposes, head over to the Protect tab and enable the Fingerprint lock option.
Now, whenever you open a locked application, you can either unlock it by simply verifying your fingerprint or by entering the unlock pattern. The fingerprints that you have registered for unlocking your device are the ones that will also work with App Lock.