A THREAD FOR NEWCOMERS!

The best defense is a good offense. And waiting doesn't mean defending. Just don't throw all your units into a single battle – sometimes the AI can be smarter than the player.

Yes, I'm gradually getting better at managing battles, losing fewer units, and in some cases, the AI lost the auto-battle, but I won. I started dividing the forces into smaller groups, which helps a lot. And of course, flanking maneuvers are very helpful, but you need experience for that.
For now, things are going well. I've won a few 1v1 matches against the AI at 160% difficulty, and now I'm playing against a 1v2 alliance at 160%. I'm gradually increasing the difficulty.
But there are still a few aspects I don't understand. I've seen that top players have a lot of heroes, at least 4, even at 115-116 days. At first, I understand why – for scouting and so on. But then, what do you do with them? I've seen them create these "chains" so that the player can clear out all the weak units in one place and quickly move the army from hero to hero. But I can't quite figure out how it's done. I just don't get it, but I feel like it's necessary.
The saddest thing is that 3-4 heroes are enough for me. As the game progresses and I explore deeper into the map, I'll create new heroes. There's also another question: is it always necessary to play with one strong hero and focus on leveling up only him, or does it make sense to level up other heroes as well? What's the best approach? Because when I choose a hero as my "leader" at the beginning of the game, it often turns out that the leader is almost on par with the other heroes in level, probably because I try to fight with all the heroes, not just one.
But there are people who claim that you should only level up one hero, who will then dominate... which I personally don't quite believe.
And of course, I constantly see that pros can clear "Go" on some maps as early as week 2 or even week 1, which I can't do. I clear it at around day 126 or 131. I can try to clear it earlier, but I can't be sure of my strength if I don't have even a small advantage. I don't want to lose half my army at "Go" and then not know what to do. The answer to all my questions seems to be: Play, play, and play again?
Correct me if my thinking is going in the wrong direction. I just want to learn how to play quickly and effectively. I don't plan to learn in 2 months, or even 6... but at least in a year, somehow.