It's a long time since I have done the tutorials but I believe they are divided into chapters.
In each chapter is the PLA that you want to open and is relevant for that part of the tutorial.
The PLA in the first chapter is an introduction one and has the complete model in it.
Barry.
One of the forum moderators.
Versions 6.5 to 25
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
Dell Precision 3510 - i7 6820HQ @ 2.70GHz, 16GB RAM, AMD FirePro W5130M, Windows 10