Here is a start:
Clickety Wickety[
^]
I don't have much to go on from your original question but you want to research Office Interop and Office Automation as a start. There is a lot on this subject on the Web and here at Code Project.
Depending on what version of Visual Studio you have you can also look into what I believer is called VSTO (Visual Studio Tools for Office)
See here[
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