Try lineageos, I have two pixels from 2016 as backups just like you and they are up-to-date with the latest security patches. I know absolutely nothing about p

Try lineageos, I have two pixels from 2016 as backups just like you and they are up-to-date with the latest security patches. I know absolutely nothing about phones/android and was able to get lineage to work in a few hours, and now it's 15 minute every couple of months to keep everything up-to-date. https://wiki.lineageos.org/ https://wiki.lineageos.org/