How to ammend a GUI made in Excel ??

Greeting All,

I have downloaded a file in "xls" format from internet. It contains a Market Analysis Questionnaire in GUI Format, you answer the question and based on your answers the file generates the graphical representation of analysis.

I have tried to view its coding, but unable to do so.

Can anyone guide me how can I amend the file and view its coding to generate a similar GUI file ?? Which software will be helpful to view its coding.

Thanks in advance to everyone.