Follow these steps to change default file open

Open Excel and navigate to the File menu.
Click on Options, then Advanced.
Scroll down until you see General.
Locate the line that says “At startup, open all files in:” Enter the path to an existing folder which you want to use as your default when opening files in Excel. A path looks something like this: C:\Users\username\My documents\Excel.
Hit OK. If needed, restart Excel or your computer for your changes to take place.

I hope this will be helpful!
Tim Paine