I recently installed elementary OS 5 Juno on my new laptop and i notice that the kernel installed is 4.15.0-65-generic and i was thinking in upgrading the kernel because I'm experiencing some issues that may be because of hardware compatibility but i don't know if upgrading the kernel may be a bad practice in EOS or may broke up some features of the OS. Does any one knows if is recommended or has experience upgrading ESO kernel? do you have some advice like use ukuu o another tool?
You can install the Ubuntu 18.04 LTS Hardware Enablement (HWE) packages in order to get a newer kernel. I've been using this on my Elementary systems for half a year or so without issues (Elementary 5.0 Juno is built from Ubuntu 18.04).
At time of typing this my main system is using 5.0.0-31-generic.
To enable HWE, type the following command in the Terminal:
sudo apt install --install-recommends linux-generic-hwe-18.04 xserver-xorg-hwe-18.04
As far as I understand, kernels do not exist in a vacuum. They rely on the rest of the system components to be compatible with their newer architecture. Even if newer kernel might be somewhat faster or have new cool features, there's some risk of instability, when you insert a newer kernel into an older system, as newer kernels might not necessarily be fully backward-compatible with the older system components.
As for me, I always want my system to be as stable and reliable as it can be. That's why I choose to never install kernel versions which haven't been approved for use with my current OS version by the OS devs.
That being said, if I were experiencing critical hardware compatibility issues which might be solved by installing a newer kernel, I would install it, because in that case it could make my system more stable (or bootable, at least).