I made the mistake of not searching in the Software Manager which would have made it so easy of course, but it might still help someone perhaps to know the console way.
This is a use case when installing "Sublime Merge Text 3" with a PPA does not work for some unknown reason. After checking the tricks of Cannot add PPA. Please check that the PPA name or format is correct, it still threw, as before:
Cannot add PPA: ''This PPA does not support jammy''.
sudo add-apt-repository ppa:webupd8team/sublime-text-3.
If it seems as if you cannot use PPA here, and you do not want to use the Software Manager (or you just forgot about it like me), how to install the program?
The question is also tagged "sublime-text" but it is just a use case for anything else.