Trains are controlled entirely via their schedules. You have to adjust the schedules of the trains so they take the appropriate direction at the switches to not run into each other (by default, they always go straight - which also means that through efficient setup of the track, you can get a double track setup with trains going one way on each without having to adjust schedules).

However, I remember the tutorials in this game being veeeeery slow and only unlocking features one at a time. I got very frustrated with the game in the tutorials because I thought it didn't have features I really wanted, only for them to be unlocked hours later. You might not even have access to the scheduling at this point in the tutorial yet, but it should be unlocked at some point.

I will try that - Thank you.