GNU/Linux Fedora 39 Downgrading Kernel Guide
The tutorial shows you step-by-step How to Downgrade Kernel on Fedora 39 GNU/Linux desktop – Step by step Tutorial.
This procedure may be Necessary only if you want to Run some Software that is Not still supported from the Kernel.
Especially relevant: Fedora Repo Do Not provide a choice Kernel Versions you’ll need: Build Linux from Source.

GNU/Linux Fedora 39 Downgrading Kernel Guide