Ubuntu 20.04: Finde Paketliste zum Installieren nicht

Ubuntu 20.04: Kann Paketliste nicht finden. Woran liegt es? Bin wie vorgeschlagen vorgegangen:

wget -qO - https://download.jitsi.org/jitsi-key.gpg.key | sudo apt-key add - OK sudo sh -c “echo ‘deb https://download.jitsi.org stable/’ > /etc/apt/sources.list.d/jitsi-stable.list”
$ sudo apt-get -y update

$ sudo apt-get -y install jitsi

Paketlisten werden gelesen… Fertig
Abhängigkeitsbaum wird aufgebaut.
Statusinformationen werden eingelesen… Fertig
E: Paket jitsi kann nicht gefunden werden.

These are two lines:

wget -qO - https://download.jitsi.org/jitsi-key.gpg.key | sudo apt-key add

sudo sh -c “echo ‘deb https://download.jitsi.org stable/’ > /etc/apt/sources.list.d/jitsi-stable.list”

jitsi-meet

I tried these two lines. Upon typing in the second one I failed. On terminal I see the following:

$ sudo sh -c “echo ‘deb https://download.jitsi.org stable/’ > /etc/apt/sources.list.d/jitsi-stable.list”
bash: /etc/apt/sources.list.d/jitsi-stable.list”: Keine Berechtigung

So I think that I have to give up on Jitsi. It seems that it can’t get installed on the newest Ubuntu.

Thank you for your advice, but this jitsi-meet decumentation is too technical for me. Far beyond my level. I cannot fololw and gave up.