, please describe the desired result you're trying to achieve and we'll do our best to make it happen. Otherwise the question is do wide, need to narrow it down.
Thank you.

Hi,
Question ican be divided in 3 subsquestions below:
1) I enabled ssh server in Ubuntu, and works fine, even in desktop. But had to leave firewall open - not sure which port was going to be used and shows it was port 11895! Why not using port 22,vwhich is a best practice?
2) Because of what was described above, is it recommended to use VNC instead?
3) Authentication: Based on user and keys? Seems to me yes, but could not find evidence

Hello, any news?

, sorry for the delay. I noticed that you work with Alexander and he has covered it via email.
Let me cover it here in case somebody else has the same questions in the future.

1. The port 22 is used when you connect to your server from the outside and the firewall permits it.
This feature is disabled by default, but if you like you can enable it:
Since the web console has the connection to the machine we can make this machine to open another port and encapsulate it to the already established connection (via which you can manage the computer from the web). And for that, we open a random port (like 11895) that you can connect to. This will work even if your firewall prevents connections to port 22.
2. Use what you think fits more,
3. For authentication, you can use login and password or login and pem file (for linux).

Thanks

Thank you, now I understand.
Best regards