hi great questions!
1.training only happens during combat. (I am reconsidering this in MIRU 2, as it stands in MIRU 1 it's a little harder than it should be to train if you get some bad rolls, I'm considering adding a training place in villages)
2. The survival book teaches you the concept of TS4. Prior to that you have no knowledge of it. You can only train skills you're aware of. That was the intention anyways.
Hope this helps! Feel free to join the discord and share your map or ask any more questions if they come up!