The days of designing websites are long gone. These days you use a content management system such as Joomla or wordpress or Drupal, install it. Then you purchase a good template e.g. from Rockettheme and all the SEO is built in.
Sellers will still dupe you into buying a conventional site (because it makes them money) and you ask (they sell).
Simplest option for you is to get a wordpres blog and convert it into a website and everything is built in.
This cannot be undone and I am sure it will be greatly appreciated.