a. You have to create a HTML help file using HTML Workshop. Create some html files and using HTML Workshop build it to .chm file
b. After creating Help file move it to your project output folder [Bin\Debug\]
c. Add a menu strip to your form and and a menu item named Help. Set the shortcut to F1 for this menu item.
d. Add code to click event of this menu item -
Process.Start("Your_Help_file_name.chm")
TO download HTML workshop -
DOWNLOAD[
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