What is the best to clean/remove unused packages/files/logs for fedora as it seems to me that a lot of files are sitting there that are useless. I tried dnf clean or … but I have the impression that nothing is happening so where I should search and clean manually? Thanks again
dnf clean is not what you need. Maybe you are looking for something like
sudo dnf autoremove, but be careful with what it wants to remove.
dnf list installed --showduplicates,
sudo dnf remove --duplicates, be careful.
clean/rotate log files: systemd/Journal - ArchWiki, Cleaning up systemd journal logs on Fedora,