[SOLVED] Upgrading 20.10 to 22.04

Hello,
I am somewhat new to Ubuntu Server, installed one a year ago, by mistake took the 20.10, and didn't know about the update windows, EOL and so on.
So, now I am stuck with 20.10 which won't update to anything.
I read about ways to update EOL systems to intermediate version, but all my attempts end in following (I tried 3 distros, Hirsute, Jammy and Impish):

Unable to init server: Could not connect: Connection refused
Unable to init server: Could not connect: Connection refused
Unable to init server: Could not connect: Connection refused

(jammy:6452): Gtk-CRITICAL **: 09:39:36.502: _gtk_style_provider_private_get_settings: assertion 'GTK_IS_STYLE_PROVIDER_PRIVATE (provider)' failed

(jammy:6452): Gtk-CRITICAL **: 09:39:36.502: _gtk_style_provider_private_get_settings: assertion 'GTK_IS_STYLE_PROVIDER_PRIVATE (provider)' failed

(jammy:6452): Gtk-CRITICAL **: 09:39:36.502: _gtk_style_provider_private_get_settings: assertion 'GTK_IS_STYLE_PROVIDER_PRIVATE (provider)' failed

This doesn't say much to me.
I managed to update the current Groovy release with apt-get update, I at first had errors, but change the soures and it updated successfully from the old-releases repository.

Does anyone know the meaning of this, is there a way to fix it? I would really like to upgrade the OS, and not have to reinstall everything from scratch.

And this is most likely what you want to see:
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://old-releases.ubuntu.com/ubuntu groovy main restricted
# deb-src http://old-releases.ubuntu.com/ubuntu groovy main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://old-releases.ubuntu.com/ubuntu groovy-updates main restricted
# deb-src http://old-releases.ubuntu.com/ubuntu groovy-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://old-releases.ubuntu.com/ubuntu groovy universe
# deb-src http://old-releases.ubuntu.com/ubuntu groovy universe
deb http://old-releases.ubuntu.com/ubuntu groovy-updates universe
# deb-src http://old-releases.ubuntu.com/ubuntu groovy-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://old-releases.ubuntu.com/ubuntu groovy multiverse
# deb-src http://old-releases.ubuntu.com/ubuntu groovy multiverse
deb http://old-releases.ubuntu.com/ubuntu groovy-updates multiverse
# deb-src http://old-releases.ubuntu.com/ubuntu groovy-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://old-releases.ubuntu.com/ubuntu groovy-backports main restricted universe multiverse
# deb-src http://old-releases.ubuntu.com/ubuntu groovy-backports main restricted universe multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu groovy partner
# deb-src http://archive.canonical.com/ubuntu groovy partner

deb http://old-releases.ubuntu.com/ubuntu groovy-security main restricted
# deb-src http://old-releases.ubuntu.com/ubuntu groovy-security main restricted
deb http://old-releases.ubuntu.com/ubuntu groovy-security universe
# deb-src http://old-releases.ubuntu.com/ubuntu groovy-security universe
deb http://old-releases.ubuntu.com/ubuntu groovy-security multiverse
# deb-src http://old-releases.ubuntu.com/ubuntu groovy-security multiverse

Can you please advise how to fix the situation?

Thank you

how did you try to update/upgrade it at all?
there is a command called do_release_upgrade to do that.

I actually found a way.
I tried with apt update and upgrade, but also do_release_upgrade, which didn't want to upgrade because it's not a supported upgrade path.
But I found this:
https://wiki.ubuntuusers.de/sources.list/
Replaced everything in the sources.list file with 21.10 entries, and then ran apt update and upgrade. The system upgraded to 21.10 without errors, and then I did do-release-upgrade, which updated to Jammy.

yes, you can do it in two steps
Anyway, if you are ready please mark the thread solved.