Keywords play major role in seo. Usually people wouldn't search by direct url, they search by keywords only. So your site must have a good keywords with high search volume and low competition.
As you begin the optimization process you have to think about the keywords best describing the content of your website and what are users more probably to use to find your site.
well, keywords are the most effective way to share your website, blog, page that what is page is all about... Keywords should be related to our site...