Drupal 8.x

I have created a small module (Drupal 8) to display an "Agree to Terms" link in the Drupal Commerce shopping tunnel.
This link displays the store's condition page.
I want to display the rendered store entity instead of the conditions page. How to do this ?
I created in my type of store, a display named "Terms and conditions". I want to make this display in a modal window when the user clicks on the link.

Here is my code :

Hello i want to create a custom content type page template only for one node i already have custom page template but from that template i want to add additional stuff for that i need custom template

I have my content type "news" now i have one news (node id = 452) for that i need different styling and script

I am really lost, and need some guidance.

Drupal is capable of doing something, that I want to leverage/exploit. 

But I can't figure out how to access this component in an isolated manner, everything seems to be deeply entangled, and every class I find that does what I need, requires 5 container classes and injections and dependencies...

So I'm out here asking to see if someone can help, before I need to literally read thru the entire code base to figure it out.

I have been working on a solution that would allow training courses to be created using Drupal as the backbone. I have elected not to use the "Courses" module and am simply using custom content types.

At this point I have the following:

Course Content Type -> which contains entity references (1 or more) to Slide Content Types -> which contain Entity references (1 or more) -> to Text or Media content (these are also custom content types). I chose not to use Paragraphs for a few reasons.

I'm using HOOK_form_alter to store a string for a taxonomy entity. Because I want to be graphical, I'm using the Form API radios type combined with special CSS for my customers to choose which color they want.

Relevant portion of mymodule.module

Dear all,

My website (http://www.evlbi.org) is showing an error (see below). I'm quite new at Drupal and am trying to understand what the problem is. I think it has something to do with the Backup & Migrate Module which is not installed. When I click on Extend to install the module I get the error.

Does anyone have any tricks on how to fix this?

Thanks!