The is widely considered the gold standard for HOI4 modding. It is an external application that provides a graphical user interface (GUI) to drag, drop, and connect focuses, eliminating the need to write code manually.
Once satisfied, export your focus tree and share it with the community through modding platforms or forums. hoi4 focus tree maker free
Tip: If using this method, download a "HOI4 Syntax Highlighter" plugin for your text editor to make the code readable. The is widely considered the gold standard for HOI4 modding