Adding keys to an .ini file

I'm running WinSCP.com commnd line. I've created a new pair of keys for a new transfer. How do I get the needed information into the .ini file?

Also, I'm using version 4.1.9

First, you really NEED to upgrade.

Keys are not added to an INI file. Use -privatekey switch of open command:
https://winscp.net/eng/docs/scriptcommand_open

For the public part of the key, see:
https://winscp.net/eng/docs/guide_public_key