Prevent kernel updates on Ubuntu

 1sagar@pop-os:/boot$ uname -r
 25.11.0-7620-generic
 3sagar@pop-os:/boot$ sudo apt-mark hold 5.11.0-7620-generic
 4linux-buildinfo-5.11.0-7620-generic set on hold.
 5linux-cloud-tools-5.11.0-7620-generic set on hold.
 6linux-headers-5.11.0-7620-generic set on hold.
 7linux-image-5.11.0-7620-generic set on hold.
 8linux-modules-5.11.0-7620-generic set on hold.
 9linux-modules-extra-5.11.0-7620-generic set on hold.
10linux-tools-5.11.0-7620-generic set on hold.

To remove the hold

1sudo apt-mark unhold 5.11.0-7620-generic

To show all held packages

1apt-mark showhold