Kernel notice - 6 kernels installed, recommended to remove 4.

[Valtam]

1.) New Kernels get installed via Install Updates. They contain newer drivers, bug fixes, security patches etc. So they are essential.
2.) The Caution warning in Lite Tweaks is simply a Category heading. It highlights the fact that you are about to make changes to your system, but there's no need to worry as the software takes care of everything. If it wasn't safe, we would not include it. Go ahead and remove those older kernels when notified.