AppleScript dialog answers

I have been searching the internet and can't seem to understand how to make this work. I have 150 computers with all different users and passwords. I wanted to create a script that will let me enter the computer name and it will give me a dialog box with the user name and password that corresponds to the computer name entered. I get to the point where I can have it ask for a computer name but I need it to give me info based on different answers. Is that part of variables or strings? If there is a tutorial that better explains this I would love it.

AppleScript dialog answers
 
 
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