@bhuvana.abhisheg Hard to say from your description alone, can you provide the steps taken before you arrived here?
I would check that the public path has been set correctly.
If you are saying that the imported AngularJS app is missing from the files service tab can you look in the following path:
(this may differ in your environment depending on your installation technique e.g. Bitnami, Docker, Source Install (GitHub), etc…)
In the path look for the example Angular JS app files, if they are here this may suggest a possible issue with webserver permissions. Please let me know where you are with this and any other additional relevant info like OS environment, installation method, error messages etc…