Please be aware there may be some caveats, certainly the change of ethernet interface names and how to manually migrate your database to e.g., mariadb-server-10.3, from an older version after the dist-upgrade has happened. The below may also suite you, I hope.
Ref the a.m. documentation including but not limited to the below in particular:
- EN - Debian 10 (buster) - Chapter 4. Upgrades from Debian 9 (stretch)
- DE - Debian 10 (Buster) - Kapitel 4. Upgrade von Debian 9 (Stretch)
- FR - Debian 10 (Buster) - Chapitre 4. Mises à niveau depuis Debian 9 (Stretch)
- RU - Debian 10 (buster) - Глава 4. Обновление с Debian 9 (stretch)
or any other language available to the docs which would suite you more.
Furthermore, please consider an upgrade to PHP 7.3 as this may be advisable for NC 16 long time support.
Happy hacking. 