I am running a chroot on chrome os and my Ubuntu version is 16.04.6. Can I update to a newer version?

I am on a Chromebook and am running a chroot. My Ubuntu version is 16.04.6 I want to upgrade to a newer version. Is this possible? If I look online, it says to open a program called update manager. For me, that program does not exist and when I type in the command to get that program, it says HTTP quit unexpectedly. Can anyone help?