Problem Supervisor Add-On

hello, I state that I am new to both Home Assistant and Linux. I installed Ubuntu 20.10 on an old Asus F9E. On the same computer I have installed Home Assistant Core. When I go to install the Add-Ons, I click Install but the installation does not start. What can I check, how can I solve the problem?

Home Assistant Core does not support add-ons. You need oner of the supervised installs for that.

Also note Ubuntu is an unsupported OS so you might want to switch that to Debian

For future reference: