"As for the question. I rummaged through the forum a lot. I think I've figured out why GM doesn't get the skills. I first got an M mage, then a GM mage, and then I managed to get a druid. And, as I understand it, that's why it happened? Does GM Mag reset?"
yes it resets. You can only be one class at a time, you cannot be Druid and GM at the same time. Druids can learn skills only to Master level.

"Now I have a couple more questions.
1. About the commanders. There are 9 classes. A class is chosen after the first kill. Then it improved even more, they gave me a choice of two points, but it was still in English, and, it seems, on auto-battle, so I didn't really understand how it happened (( There was, it seems, a magician. I learned to change spells. The question is, under what conditions does this increase occur? And do all 9 classes have it?"
Of the 9 commander base classes, 8 have two specialization options available. The specialized class is not always better, but rather more suited for a certain situation or playstyle. Overall I wanted to increase the gameplay possibilities.
The base class can be chosen when the first kill with your commander has happened. After 30 kills you can choose the specialization, but your kill count will be reset. Part of the bonus that has been acquired so far will be transferred to the new class.

"2. Previously, skills were highlighted in the Hero Class Point Table, but now they are not. Is there something wrong with me?"
They should be highlighted of your hero has learned them, if they are not it seems like a bug.

"3. I'm sorry right away, a little off topic, but maybe someone can tell me.
After reinstallations, the flags disappeared from the captured mills and gardens (they used to be, I play with the capture option). Why could this happen?"
No idea, I must check this ingame.

"P.S. Now I was playing, I couldn't use "joy" in battle. This is because of the "badge of courage" that I recently picked up, as I understood. Previously, it was immune to enemy mind spells. Now from your own people?"
The badge of courage is bugged in SoD and this is transferred to WoG. The immunity on this artifact was not intended, I would like to have it removed. But to my understanding, it should not apply to own units.