I'm missing the 'Structure' option in the 'Insert' toolbox and some of the tags used to create the page 'Bayside Beat Cable Cars' eg the <header> and <nav> tags.
I'm using Dreamweaver CS6 (Full Retail Version) purchased from tehtechkings.com. It's currently in Trial Mode. Apparently the Product key can take up to 24 hours to arrive!!!
Does anyone know if these limitations are because I'm using Dreamweaver in Trial Mode?
There are no limitations in a trial version. The reason for the different options in the Insert panel is the version of Dreamweaver that you're using. The tutorial was created for Dreamweaver CC (the Creative Cloud version).
Since you're using Dreamweaver CS6, I recommend that you try following my written six-part tutorial for CS6: https://www.adobe.com/devnet/dreamweaver/articles/first_website_pt1_cs6.html. It uses a different website design, but covers all the main features of Dreamweaver that you need to know to get started.