I can't install apache2 for the first time on ubuntu 24.04

I suppose Ubuntu renamed the repositories in /etc/apt/sources_list.d/ from *.list to *.list.distUpgrade during the upgrade.

You should edit those files and modify them to be sure they are using noble as distro and once done, rename them from *.list.distUpgrade to *.list. Maybe you should delete and add again ondrej’s ppa repositories (for apache2 and php).