Question ?

[Moiz2002]

How can we use fingerprint lock like watsapp has for every other apps ?

[aakashnawab7]

You have to use third party apps from store for that.
Search AppLock in playstore and try few apps. Select one which suites you best.

[Shahzaib-Ali-hai]

Open the “Settings” app on your Samsung device.Scroll down and tap “Apps.”Tap the three dots in the top right corner of the screen.Tap “Default apps.”Tap “Device assistance app.”Select “S Look” from the list of available apps. Try this if not then we don't have by samsung.

[thisissheraz]

Why you need on every app? Just lock screen it

[Shahzaib-Ali-hai]

Good point

[JimmyAdam]

It is only allowed when app supports this function