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Upgrade old version of Debian
(lemm.ee)
Debian is a free operating system (OS) for your computer. An operating system is the set of basic programs and utilities that make your computer run. Debian provides more than a pure OS: it comes with over 59000 packages, precompiled software bundled up in a nice format for easy installation on your machine.
Yes that's the recommended path.
Information on how to upgrade can be found in the official documentation:
https://www.debian.org/releases/stretch/amd64/release-notes/ch-upgrading.html
https://www.debian.org/releases/buster/amd64/release-notes/ch-upgrading.html
https://www.debian.org/releases/bullseye/amd64/release-notes/ch-upgrading.html
https://www.debian.org/releases/bookworm/amd64/release-notes/ch-upgrading.html
As others pointed out it might be a PITA. Depending on your installed software and configuration a new install might be easier.