I'm not very skilled on apple, but I need to perform a Remote Desktop into my vpn network. How do you configure the app on an iMac
Follow the instructions here for MacOS.
You may need to reorder the network adapters in order to force data across the client VPN. Here's what I do:
After the VPN connection is created, change the priority order for the connections:
A better option, following the advice of @Nash, would be to make a dedicated location so that you don't have to fiddle around with changing service orders based on what networking you are doing.
Another top tip for locations:
You can set up locations based on network requirements, say for example you can have an Ethernet only network location by removing all other network interfaces by judicious use of the minus button.
Another good use of the locations is to check to see if networking issues can be troubleshot down to an interface. Say a client can't connect wirelessly:
Make a test location, do the Apply and see if this resolves.
If it does all you have to do, in the original location, is remove and re-add the errant interface (in this case the Wi-Fi, with - followed by an +) and don't forget the Apply.