Everything hosseinimr93 said is correct.
Regarding this question:
Will device ask for passphrase every time immediately after you have entered pin/password (to unlock device)?
The device always asks you for a pass
word which you enter on the device itself, as normal.
In the software, you will be prompted to enter the passphrase after you set it up. However, you can 'disable' the passphrase feature again, effectively making that wallet hidden in the sense that there is no prompt unless you activate this option again.
Does it mean that if you enter 1000 wrong passphrases, then the wallet will not be reset or wiped, it will just open 1000 different wallets?
Basically, every passphrase is valid and opens a different wallet. That's what some companies call a 'hidden wallet' or maybe also 'plausible deniability' feature.
Someone can pressure you into giving them your passphrase, if they notice that the main wallet (without passphrase) is empty. You could give them any random word, which just unlocks an empty, unused wallet, but to make it more plausible you could deposit some funds in there.
For instance, unlock your BitBox02 with the passphrase 'gorilla', deposit $10 of BTC and use that passphrase if you're in such a situation. They can see 'ok, that's all he got', take the money and leave you alone.
So making a typo (I don't mean forgetting or loosing passphrase) is not dangerous itself no matter how many times you made a typo?
Exactly; because there is no 'right or wrong passphrase'; all of them are 'correct', just that almost all wallets that are 'behind' those passphrases, are empty. But they're all valid!
Hope it makes sense.
One more thing: do remember to backup your passphrase! As soon as you start using passphrases, your seed isn't a sufficient backup anymore.