Just my header showing up in Explorer

The problem is that your theme has some problems. Some page elements are missing like the “doctype” header, when pages are improperly structured or have structural errors, some browsers are better at guessing than others, sometimes their guesses work better than others.

I used a validator program at https://validator.w3.org/
It gave me this report, the first and most startling thing about it is that the doctype field is missing.
https://validator.w3.org/check?uri=http%3A%2F%2Fwww.pdqfirewaterdamage.com%2Fwater-damage-morristown-nj%2F&charset=%28detect+automatically%29&doctype=Inline&group=0

Suggest that you get support from your theme author.

As you use a commercial theme/plugin and need support, please use their official support channel. We feel they are best equipped to support their products.

https://themeforest.net/item/bridge-creative-multipurpose-wordpress-theme/7315054/support

Commercial products are not supported in these forums. .

There’s also a self signed SSL certificate installed and you have mixed content issues that need fixing or they will be blocked.

HSTS needs to be enabled to ensure the website is only deliverable over a secure connection i.e. https:// and not https://.

It doesn’t show properly in Firefox either as there are loads of errors, again it’s mixed content issues.

Like what Ross said there’s no Doc type and Edge is reporting it as a problem.

Did the theme come like this or has someone been playing with the files?