Forty-plus lessons on their own are a library; a path through them is a program. This trail runs from "what's a PLC?" to job-ready automation engineer in one climb through five altitude bands, and each band rests on the one below it. Follow the line down. Every medallion opens its lesson and lights up once you've been there, and at the summit you are a working engineer.
Finish the climb and you can read a P&ID and a schematic, wire a panel and reason about sinking vs sourcing, write structured logic with the right POU, scale an analog signal, tune a PID loop, size a motor, build an HMI, place MES and ERP, defend the network and, most of all, troubleshoot a dead machine methodically instead of guessing. Someone who can do all of that is past beginner level and working as an engineer.