Getting started with HTML, Doctypes, Headings, Paragraphs, Text Formatting, Anchors and Hyperlinks, Lists, Tables, Comments, Classes and IDs, Data Attributes, Linking Resources, Include JavaScript Code in HTML, Using HTML with CSS, Images, Image Maps, Input Control Elements and SVG
books.goalkicker.com
Getting started with CSS, Structure and Formatting of a CSS Rule, Comments, Selectors, Backgrounds, Centering, The Box Model, Margins, Padding, Border, Outlines, Overflow, Media Queries, Floats, Typography, Flexible Box Layout (Flexbox), Cascading and Specificity, Colors and Grid
books.goalkicker.com
Getting started with JavaScript, JavaScript Variables, Built-in Constants, Comments, Console, Datatypes in JavaScript, Strings, Date, Date Comparison, Comparison Operations, Conditions, Arrays, Objects, Arithmetic (Math), Bitwise operators, Constructor functions, Loops and Classes
books.goalkicker.com
y por ultimo
https://books.goalkicker.com/PHPBook/
luego ve a wordpress.org y con la documentación puedes ir haciendolo.
Si prefieres el camino del dolor:
https://roadmap.sh/frontend ( 1,1,1,2,1,2,1,2,1,5,1,5,13,1,5,15,6 hasta javascript )
https://roadmap.sh/backend ( 1.1.2.2.4.5.1.4.1.4.1.5.6.1.1.4,1,5,1,5 hasta php )