Start with Category and editor decide behaviour: an input type's name tells you nothing, and the category and editor tell you everything, including what the code editor allows. Select options, keys and design tokens covers the type you will create most often, the select whose keys become CSS classes, and how to keep a site from collecting dozens of near-duplicates. Record and records pickers covers fields that point at other content.
The regular expression, maximum length and default content an input type can carry are set alongside the layout area's own rules, so they are covered together in Validation and default content.