Confused about templates

The short answer to your question is Yes, you have to stick to a WordPress theme if you use WordPress as your content management system.

The longer answer:

Many of the themes and such that you're seeing are basic HTML. There is no back-end for managing those files. You have to know HTML/CSS to add stuff to them, change the look, etc. (Dreamweaver is Adobe's HTML editor software). Others are for Joomla, or Drupal, etc. which are content management systems like WordPress, just of a different flavor.

Let me try a metaphor that may help you out:

Think of your website like a car. The Content Manager is like the engine of the car. It makes the thing go. It has a certain way of interacting with all of the other parts of the car. The theme is like the car's chassis/body. It creates an interface for people to work with.

You're going to have a tough time putting a Chevy engine into a Nissan. They're laid out differently, they fit differently into the engine compartment, they're just not going to work together, and the car isn't going to go anywhere.

You've got a Chevy engine. You need to provide a Chevy chassis/body or you're going to have to do some serious work to convert something else to work with the engine you've got. That's more work than you want to take on by yourself without professional help, I assure you. (In this metaphor, HTML templates for Dreamweaver are like a bicycle...)

I recommended in your other thread, and somebody else recommended here, that you check out the stuff over on Themeforest.net. They have tons of great WP templates that don't look too "bloggy" and that can help you feature your content, and show off the products you've selected.

I would encourage you to also start planning a budget to get a professional to help you build something that looks more like what your vision for the site might be. It may be something for the future, but I assure you that you're going to spin your wheels for a long time, and wind up with a lot of frustration if you don't start planning for that now.

there are many themes out there and if you don't want a "bloggy" looking site you can modify it... css and php

if you don't know css or php you can maybe ask a friend... you don't need to go ahead to professional designers... better you can slowly and gradually learn it by slowly and gradually tweaking it.

1. make an overall picture of how your site must look like... since your site has three columns (1 for main content and 2 for sidebars) look for a theme that has the same features
2. download and install that theme.. it may not matter if they don't have the colors that you want because you can edit it...

installing the theme and redesigning it won't affect your content.

I get my theme's here newwpthemes (dot) com/ and then I redesign them by tweaking on the css code and php. As an example, this is the orginal template of the new site i made newwpthemes(dot)com/wordpress-theme/prestij/, I tweaked it and turns out like this (second site on my signature). It could take days but it is also an investment to your skill

maybe you're not a techie (I'm not but somehow learning hehe) but the internet has so much resource and that you can find answers by just searching it on google. as an example is that when I see in a css code a hex color "#00BEF2"and don't know what color is that I just type it on google.