Don't permit root login. That is like wearing a 'kick me' sign. Transfer files as a regular user.
Appears to me your code has some gibberish, you are pasting together advice from different sources. The last 2 lines betray you there. These are old style service launchers. In current Ubuntu, you'd run
sudo systemctl start ssh
Since you mention ufw, it makes me wonder if you are also running other security. If you have fail2ban, then your SSH login might be blocked by your security because you have too many failed tries. If you did some cutting and pasting in /etc/hosts.deny, that could cause same effect.
Here is what I would do. Suppose you are logged in as firstname.lastname@example.org and you have account same user name on other system. Maybe if you are playing in 2 systems at home, you have IP numbers like 192.168.0.1 instead of system names. I guess the numbers are more likely.
On other system, Turn off UFW and other blockages like fail2ban, then go to your email@example.com system. Try
To make sure connects are ok
To prove login works. Then log out, try
scp file.txt firstname.lastname@example.org:
That will copy file.txt to other system. Then login again over there an make sure file is there.
Keep it simple, don't copy/paste code you don't understand from websites.
While on the other system, do the UFW config. Do not run iptables directly. UFW is a simple interface to iptables firewalls. Turn on the UFW firewall again. Log out. If you strangled yourself with errors in iptables, perhaps this is bad enough to warrant a restart.
Try to log in again. If rejected, then your UFW setup is bad, have to walk over to other system, try to fix over there, you are not allowed to log in.
Please note here that the ssh programs on home.com are needed, but at this stage you do not need change the config. Outgoing ssh is generally configured sufficiently. On other system, config generally does not need alteration. You make a disastrous mistake by allowing root login, don't cause trouble for yourself.
I realize that if you have account named "user" on both accounts, it is not needed to type "user@" in these commands. I write this for clarity to new users.
If problem is that fail2ban is blocking you and your user is in jail, I wrote notes on how to clear it a few years ago (http://pj.freefaculty.org/blog).
I suppose my 'old man' message is try to understand lines you run, and be more careful about copying instructions for other distributions or times.