I'm gonna answer this even tho it's a month old, perhaps it will help someone else. Terminal way:
1. In the left pane "Groups & Files", expand the "Products" folder and right-click -> get info on the name of your program.
2. At the top now you will see "Full path:" and a pathname, select everything here up to the last slash so for example if your full path is /Users/Sinth/Desktop/objc/testprogram/build/Debug/testprogram
you want to copy everything expect for the last part leaving you with /Users/Sinth/Desktop/objc/testprogram/build/Debug/
3. Search for terminal.app in spotlight (control + space) and run it.
4. In the terminal type cd followed by the path you copied (surrounded by parenthesis) and hit enter.
Using the preceding path: cd "/Users/Sinth/Desktop/objc/testprogram/build/Debug/"
5. Now you can do the command for the program like so: ./testprogram src dest
Note that the ./ in front of the program name is needed here, and of course you will need to replace testprogram with whatever you named your program.xcode way
In the left pane "Groups & Files", expand "Executables" and right-click -> get info at the item there.
In the window that shows you can add arguments from the "Arguments" tab.