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I'd recommend opening in a new tab. Part of that is personal preference, but I can't see any case in which it's a good idea to move someone off your site in that situation.

In a sitemap you include every URL that you want the search engines to have crawled + indexed. If you're running your blog on WordPress it would be good to look into the Yoast plugin for example who will take care of this for you automatically. After this you'll submit your sitemap index file usually to Google Search Console in order for the search engines to pick up the new pages.

If you wish to see performance of KWs or pags you can see few tricks from today post in Moz: https://moz.com/blog/single-best-seo-tip-for-improved-web-traffic Yes - SearchConsole is heavy involved in process.