I’m new to this and just wondering the main difference between WordPress, Site Templates and PSD Templates to be purchased if there is a difference. How can I know the best type for my purposes?
If you’ve HTML/CSS knowledge you can buy PSD/HTML template and adjust to your needs. These kind of premium templates doesn’t have content management system and cannot be edited via admin panel, but they’re cheap.
However if you don’t have knowledge in coding I would suggest you to buy WordPress theme. You’ll get professional theme that you can easily edit without any special skills.