The best way to make the modules stick is to build something. These five projects take you from your first game in Godot and a Unity beginner project, through a complete 2D platformer, to a 3D game in Unity and a larger 3D RPG in Godot.
Each one is a code-along video, so you can pause, build it yourself and change it into your own game. Pick the project that matches the module you've just finished and come back for the rest.
Brackeys walks you through making your first game in Godot from scratch, a friendly starting point once you've picked an engine.
Game Maker's Toolkit introduces the Unity editor and C# scripting by building a Flappy Bird-style game from an empty project.
A zero-to-shipped beginner project: build a tile-based 2D platformer in Godot 4, from levels to exporting your finished game.
The Game Dev Cave guides you through building a first 3D game in Unity, a good follow-up to the 3D module.
A long freeCodeCamp course by Coding Quest on building a 3D RPG in Godot, covering the kind of gameplay systems found in larger games.