Apple TV password

I don’t wanna share the password

And you shouldn’t.

What are you considering to share?

• To share Apple TV+, use Family Sharing, which keeps all accounts separate, but grouped.
• To share the Apple TV box, use multiple accounts.

How do I set up a different password for Apple TV

By having the Apple TV on another iCloud/Apple ID account, which will remove the Apple TV from the network of devices and services it uses as part of your current iCloud account.

No you don't need to at all. Your Apple ID and iCloud has one set of credentials. You need to use those credentials on the Apple TV to be part of your account.