first thing it is kernel not kernal
in application manager ( the safe way ) look for package "linux kernel for power user " and extra-devel and testing repos must be enabled.
every here installed that safely but im not responsible if something happened

i installed the kernel power 50. it says something will be removed and all. i was afraid it will cause more damage to do it so i kept it like that.btw i did update the phone using nokia software updater today. but that din help. i lost all data, neva mind. but the update was successfull and this thing din change

first thing i suggest you to go and eat because your eating some letters from the words you are writing "just kidding "
if you gonna be afraid you will face more problems and to help your self more the search button on the upper right of the screen try searching when you want to install anything afraid you