Module development and code questions

I'm a new Drupal user (though decades of other dev experience) looking for advice on best practices.  I need to develop a multi-client web application with defined (but client-extensible) data model, along with forms for managing data entry and API endpoints to use that data.   Basically I need to build an entire web-app that can be deployed multiple times to different independent clients, but still allow them to take upgrades and bug fixes.

Question to drupal ninjas here. Is it possible to make hook_node_grants() to use "AND" condition from realm instead of "OR"?
What I mean is if for example I have realm1 and realm2, the current functionality is that if the user has gid(grant id) to at least 1 realm, the user has a grant view. What I'm trying to do is to change it to an "AND" condition so that the user needs at least 1 gid from realm1 and realm2 to have grant view access.

Thanks a lot!

Hy guy's,

I'm a beginner in the world of Drupal. Currently, I work on a new module with the "quiz" module (from opigno and Drupal 7) for my internship.

So I need to get the score value at the end of the quiz module inside my module.

In the quiz module, the value is: 

Hello,

I'm starting to learn Drupal and all the things you can do with it, so i have this project i'm working on its something for a financial website. i have some basic knowledge of Html and CSS and i understand PHP but can't write any php or anything. 

Short explanation: The calculation is used to give a small business owners insights on how they are preforming and if they could have done better. The base calculations are in an excell sheet, we only need to fill in 3 tables of numbers witch then will calculate outcomes. these outcomes are shown in different charts.

Can someone provide me example/help with sending an html formatted email programatically.

Can anyone help based on Form Value, how to disable sending an email that has already been configured within admin/config/workflow/workflows/manage/case_workflow/transition/publishing_review_to_publish . I am using workflow moderation.