I’m interested in how to build a team of young players when they gain almost no experience by coming on as substitutes in matches. How many seasons will it take me to defeat an elite bot team? For me, it’s not normal to invest money and still be beaten by bot teams, and for players to play a match but not gain the same amount of routine. There is some scattered information about the game, but almost nothing becomes clear until you face the reality yourself and figure out what you actually need to do.At what time do the new youth players appear?
Is it at a different time for each country, or do they appear at the same time for everyone?

Your main problem against elite bots, aside from the fact that, like me, you're at the limit of competitiveness, is a tactical one.

The tactics are explained in the game's help section. But also, Nicmo recently published an excellent article on his blog detailing in more depth how the match engine works.

That blog post was live and appeared as an ad on your homepage a few days ago.

I would start there, by understanding the game engine.

Secondly... you're referred by Chantilax, a player who's been in the game for a while and is at the elite level, so take advantage of this to talk to him a lot more. Learn about how to train players, how to choose youth players, etc.