Write a unique content which is good for SE, for links, for visitors. Search engines value new information that has not been published before. A site based on materials taken from other sites is much less likely to get to the top in search engines. As a rule, original source material is always higher in search results.
While creating a site, remember that it is primarily created for human visitors, not search engines. Getting visitors to your site is only the first step and it is the easiest one. The truly difficult task is to make them stay on the site and convert them into purchasers. You can only do this by using good content that is interesting to real people.