I've gotten as far as turning on SSH
You have ssh access now, right ? You must have username/password of the server, not your Godaddy account username/password.
downloaded something called openssh-7.2
You should use Putty, or Xshell to connect to your server via SSH, with your ssh username/password.
After you log in, you will have a shell access.
Then you can try my client: GitHub - acmesh-official/acme.sh: A pure Unix shell script implementing ACME client protocol
you just need 3 minutes to use.
If you don't have Git installed on the server, you can download the source code https://github.com/Neilpang/le/archive/master.zip
curl -LO https://github.com/Neilpang/le/archive/master.zip
or
wget https://github.com/Neilpang/le/archive/master.zip
Then unzip the source:
unzip master.zip
Then install:
cd le-master/
./le.sh install
Then you can issue cert now.
please refer to the readme: GitHub - acmesh-official/acme.sh: A pure Unix shell script implementing ACME client protocol