1) Is there any hardware wallet support Multi coin (at least bitcoin forks)?.
TREZOR has supported both forks and provided a convenient splitting tool. They have some alts too if you're into that.
2) how can get private key from these wallets?.
They're HD wallets, so the collections of words (the seed that they give you) is used to generate your private keys. It can be exported and used in several other wallets.
3) can edit settings to get more than 1 wallet for 1 device?.
On the TREZOR, while you have only one seed, you can add different passphrases (an additional string which can be used to strengthen the security of your seed) to create several different wallets.
You can also have different accounts to sort your funds differently, but these aren't separate wallets as such.