ssh is the program you use to connect to a remote machine
sshd is the daemon running on your computer that allows remote machines to connect to you
So by editing sshd_config, all you did is tell your computer to listen for incoming connections on some new port. It doesn't change how you connect to other machines.
You just need to specify the port when you call ssh, such as
ssh -p 45678 firstname.lastname@example.org
And if you want to scp files to the computer
scp -P 45678 files email@example.com:/path/to/destination/