I'm hardly a git expert (though I do use it occasionally), and I've never used GitLab. It seems like the critical problem is:
[Michael@devServer first-project]$ git push -u origin1 master
fatal: 'root/first-project.git' does not appear to be a git repository
fatal: Could not read from remote repository.
It seems like you're trying to connect to mysite.com as user "Michael", and then trying to access a repository in root's home directory??! This seems a little bit nonsensical to me.
I guess the question is, did you ever actually create a bare repo on your server (mysite.com) that you were able to clone onto your workstation? If so, you shouldn't need to manually add a remote, it should be set up for you automatically. It doesn't look to me like you were able to do this correctly, which is why nothing else is working. What you need to do is someting like:
# server side
email@example.com$ git init --bare /home/serveruser/myrepo.git
# workstation side
wsuser@workstation$ git clone firstname.lastname@example.org:/home/serveruser/myrepo
wsuser@workstation$ cd myrepo
# add files, make changes, commit them, etc.
wsuser@workstation$ git push