I am not able to find my paid app on my iPad even after successfully downloading it

Check to see if you have restrictions enabled. If the app falls in to the restricted category, it will be hidden.

Also, if you just pull down from the home screen to open Spotlight, you can search for it.

If you can find the app on the App Store, if it successfully downloaded it will say "Open" next to it. The Open button should do the trick. If there is a cloud download icon or a price, you have not successfully downloaded the app.