Our documentation is a community effort, published via a Discourse forum hosted at discourse.ubuntu.com. We welcome corrections and enhancements as well as suggestions and constructive criticism.
You can modify (almost) any page by visiting the Discourse Documentation category, where each documentation web page corresponds to a Discourse topic. In addition, every web page has a link that leads directly to its corresponding topic. All you need to do is sign up on the forum and follow the Documentation guidelines.
If you’re unsure of your intended contribution you can leave a post on the topic in question asking for guidance.