This article covers how to update your Linux Kernel. In fact, Upgrading the Linux kernel can be difficult, especially for new Linux users. In Linux Mint, however, it's possible to upgrade to a newer kernel with zero hassle.
To keep your kernel 5.15 up to date, you will use the apt update and upgrade commands to pull updates from the PPA repository just like any other package on your Linux Mint system.
To check for updates and upgrade:
$ sudo apt update && sudo apt upgrade
Remember, for any kernel updates, and you will need to reboot your system.