Hello everyone , is there a way to create a box which prompts for password on the first screen and when the password is entered user enters the app ?how can i do it ?

Look up each part: How to create a box someone can type into; How to read it when they're done; How to go from one scene to another. There are answered Qs about each of those here. Write and test one, then try the next part by itself, then combine when you know how to do each one.