Can iPhone 7 passcode be different from keychain passcode on the same iPhone?

Can passcode on iPhone 7 be different than the keychain passcode on the same iPhone?

The passcode on my iPhone is different than the passcode I use to download from the App Store. Can I have a different keychain passcode, than the passcode I use to open my iPhone?

I want to have 3 separate passcodes:

#1 to open my iPhone 7;

#2 to download from App Store

#3 to access my keychain passwords

I already have #1 And #2; is there a way to have #3?