When first you open PowerPoint, you are asked to decide how you would like to create your presentation. You have three options:

Auto Content Wizard asks you some questions, and then creates your slides for you. This produces a very stereotyped or 'canned' presentation, and should be avoided at all costs...    Do browse through the options, though, because they're useful for getting ideas.

When you have just started, using a template produces slightly better looking presentations, but once you know what you're doing, you'll find that few templates meet your needs exactly, and you'll end up modifying them anyway. 

Fortunately, there is an option to create a 'blank' presentation, which gives you full control over the look, feel and content of your presentation.