Landing Page Template Integration (Template

Hello,

I am trying to convert an HTML landing page into a page template so that I can simply select it when creating new pages. and all the CSS and scripts and hopefully content divs and mages will be automatically applied.

So far I have created a new page template which is added into my child theme. I have added the javascript and css files and images into the child theme.
I have tried to use a plugin to insert header scripts and CSS reference as well.

The problem is that the display is highly flawed.

Below are copies of the code as I have it right now for 1. the separate landing page html file which I a trying to apply. 2. The custom-template.php file as it is so far.

Landing page I want to copy:

[Large code excerpt removed by moderator per forum rules. Please use the pastebin for all large code excerpts. It works better anyway.]