Hi Rajesh,
First of all Kudos for your 1st Unity Project,
Positives - I like the Background and the Music which you have added in the main page. It is nice to see that you have added button click sounds and rollover color changes. You have used the asset store properties which show the level of usage of the unity software.
Improvements - You could have added more functions into the Game scene for the rocket.
Good Luck with your upcoming projects,