New to Web building

I have downloaded zc, and configured all of my shop settings (payment, shipping, etc). Now I am stuck on trying to figure out the customization. I just don't get any of it. Where can I get a crash course on html or php or whatever I need to know? I have always used simple templates in the past, and have no knowledge of where to even find files.
I managed to change a banner in the banner manager, and it changes every time I refresh my url: nettlesjewelry.com

I apologize for the basic questions. I am just ready to give up.

You don't necessarily need to know HTML or PHP to customize your template, depending on what you want to do.

You will need to learn something about CSS, as many changes to the appearance of your shop can be made in your stylesheet. (https://www.w3schools.com is a good place to start learning.)
You will benefit from getting Firefox and its Web Developer extension for finding out what to modify and trying things quickly.

The first thing to do, after studying the FAQ/tutorials on templates, is to search the forum, then if you don't find help, ask a specific question (preferably with a link to your site) so we can give specific advice. We don't want to just tell you everything you might need to know; that would overwhelm you and tire us out.

This list is a bit outdated, but it'll give you an idea where to start to create a very basic custom template (you can build from there):

• includes/languages/YOUR_TEMPLATE/english.php
• includes/languages/english/YOUR_TEMPLATE/index.php
• includes/languages/english/YOUR_TEMPLATE/meta_tags.php
• includes/languages/english/YOUR_TEMPLATE/header.php (to change the logo)
• includes/templates/YOUR_TEMPLATE/template_info.php
• includes/templates/YOUR_TEMPLATE/common/tpl_header.php
• includes/templates/YOUR_TEMPLATE/common/tpl_footer.php
• includes/templates/YOUR_TEMPLATE/images/logo.gif
• includes/templates/YOUR_TEMPLATE/css/stylesheet.css

Anywhere you see a /classic/ folder, you can create a folder for your custom template. You can copy the necessary files from either the /classic/ folder, the /template_default/ folder or the parent folder.

Edit includes/templates/YOUR_TEMPLATE/template_info.php to give your template identifying information so you'll recognize it in the admin under tools->template selection.

Where do i find these folders?

In your site's hosting control panel. (Probably under /public_html/ or /www/ or /htdocs/ or the like.)