Outcast's Path

Yes, exactly. I received a task from the main human to capture the Orcish castles. A message appeared saying that I needed to visit the Elves. The passage to the bridge is blocked (where the Elf stands and gives quests).
An army of Ents was guarding the Cloak of Silana and something else that looked like a Ring of Warning. But these aren't valuable artifacts; you can buy more serious ones in the castle...

I didn't have that quest (probably due to low reputation).

Most likely, that's the case. I currently have a reputation of 90, and I haven't completed the quests about the Grail, the Mead Hall, and I haven't delivered 10 barrels yet – that's another 12.

So, before, I could go to the Elf, but after receiving the quest, I can't? That's impossible.

Added 1 minute ago

I have a simple question: where can I get wood and ore to build a castle? The other resources are still found near strong armies. I think I chose the wrong direction for my campaign again.

1) Resources are scattered around.

2) As you gain reputation, mines in the cities will be transferred to your ownership; the first ones will be wood and ore mines. After that, you won't have any problems with resources. You can gain control of the mines the fastest from the Elves.

Added 14 minutes ago
Reputation:

With the Orcs:
- above 25 - a supporting hero is assigned in the city + the ability to take the first main quest
- above 50 - 2 mines are assigned + the ability to take the second main quest
- above 75 - 4 more mines are assigned + the ability to take the final main quest

With the Humans:

- above 50 - a supporting hero + a city + 2 mines are assigned
- above 75 - 2 more mines are assigned + the ability to take the final main quest

With the Elves:

- above 50 - 2 mines are assigned
- above 75 - 2 more mines are assigned + the ability to take the final main quest