nemozone

https://web.archive.org/web/20181001000000*/https://www.ncsc.gov.uk/guidance/eud-security-guidance-ubuntu-1804-lts

https://web.archive.org/web/20180731074521/https://www.ncsc.gov.uk/guidance/eud-security-guidance-ubuntu-1804-lts

https://web.archive.org/web/20180731074521/https://www.ncsc.gov.uk/guidance/eud-security-guidance-ubuntu-1804-lts#rest

https://web.archive.org/web/20180804151830/https://blog.ubuntu.com/2017/08/11/how-to-sign-things-for-secure-boot

https://web.archive.org/web/20180804151829/https://wiki.ubuntu.com/UEFI/SecureBoot/DKMS

https://support.google.com/a/answer/6328676?hl=en&ref_topic=6079327

Disclaimer: This is a gov.uk site, use tor or something to protect your privacy!

https://www.ncsc.gov.uk/collection/device-security-guidance/platform-guides/ubuntu-lts

The step-by-step instructions are unfortunately gone, :( But there is still the GitHub post script

https://github.com/ukncsc/Device-Security-Guidance-Configuration-Packs/blob/main/Linux/UbuntuLTS/Ubuntu-LTS-post-install.sh