Had a few questions regarding authentication test cases and couldn't find an answer in the the docs. 

1. If an app like Zoho Creator requires authentication before providing access, do I need to create a login function and add it to each test case?

2. Where can I find docs on how to set up MFA for test cases? I'm using Zoho OAuth and it's not referenced in the docs: https://help.zoho.com/portal/en/kb/qengine/user-guide/settings/mfa/articles/mfa-in-test-cases#1_Overview

3. If I use a username and password to authenticate, how do I keep my password secure in QEngine? I see variables, but the only option is string, variable, and boolean.