I'm worried that I would lose my 6 million gold I have in my storages. Can other players steal my gold from me?
You can lose gold, elixir, and dark elixir (but only if dark elixir is unlocked for you). You can also lose trophies. Trophies aren't so much a resource though, rather a determination in your overall rank.
Up to 20% of Gold/Elixir/Dark Elixir can be stolen from storages but the maximum is 198,000/storage.
Up to 50% of Gold/Elixir/Dark Elixir can be stolen from mines/collectors/pumps and is capped by the storage capacity of the generator.
1000 of each resource can be taken from the town hall.
You lose trophies based on the attackers level. If the attacker is a higher level than you you’ll gain more if you win and lose less if you lose. If the attacker is a lower level than you you will gain less if you win and lose more if you lose.