How To Enter The Novice Tutorial?

It's my first time to play. I disabled most DLC because of lack of space. I heard that the teaching level is also DLC, but I don't know its name.

 

There is the Academy - assuming you have it and some locos have a Tutorial

 

This game should have an initial DLC, right? I bought the complete game directly, and there are hundreds of DLC, which add up to nearly 1TB. The price is that I can't tell which ones are the initial DLC. What I need now is a teaching level to help me understand how to operate this game. Just like in TSW, the first time I play it, I will tell you which buttons to press.

 

Not sure why yu have bought the game with "hundreds of DLC" -
Most people stating in TSC buy the base game that comes with three routes and different trains.
In your Railworks Folder is another called Manuals - have a look in there.

https://store.steampowered.com/manual/24010