Thanks.
The domain.com/setup helped.
I completed the setup and the MODX Dashboard seems to be working again.
The
http://rtfm.modx.com/revolution/2.x/administering-your-site/upgrading-modx
upgrade needs to be clearer with the steps I mentioned above.
I can't find the webhost's Control Panel.
I am familiar with cPanel from a long time ago, but this Webhost doesn't have cPanel.
I couldn't easily find a file manager, so stuck with the FTP.
I also can't SSH into the Webhost, as the Webhost doesn't allow SSH.
I'll try Git, once I update some pages, to get the website back under control.
P.S. Any tips on editing the MODX website locally, rather than live.
It scares me and shouldn't be edited live.
I'm used to Git, SSH and CLI, so it took a long time to figure out the MODX GUI navigation and bugs.
Ok, thanks for the tip domain.com/setup.