I'm not sure if I'm just missing something, or if it is not available. I can hit F1 or the '?' all I want, but nothing happens. No error, nothing.
Help files would be really useful, I think. The options dialog is missing, so I cannot check the paths to see if there is a valid path to a CHM.
I agree that hitting the "?" icon should bring you to the help (as it does in Inventor for instance).
Use the dropdown menu under the down arrow instead and use menu "Fusion wiki Help"
Once you are in the help wiki , you can see that Fusion does not have F1 as a function key.
Here is the list of Fusion's shortcut keys: