Help upgrading from 1.13.0 to 1.22.0

A couple of years ago, I used the Linode Marketplace to deploy Gitea 1.13.0 to a new server. Now, Gitea is up to 1.22.0, and I would like to take advantage of the new features. The docs recommend checking for conflicts. I’m a beginner at all this and would appreciate some help working through it. You can find my Gitea install here:

Also, is this guide usable? HOWTO Forgejo upgrades, a guide for admins - HOWTO - Gna!