I've found a brilliant series of nine YouTube videos, by Robert Wimer,
which I recommend you have a look at. They cover most aspects of how
to use WordPress ...

Part 1   https://www.youtube.com/watch?v=Fq39O_Rb-pY&feature=related
… the differences between WP.org and WP.com

Part 2   https://www.youtube.com/watch?v=qLx2p6x_VIM&feature=fvwrel
… all about the Dashboard (your main control centre)

Part 3   https://www.youtube.com/watch?v=3y00aTG3qoQ&feature=fvwrel
… customising the general settings

Part 4   https://www.youtube.com/watch?v=XtsJzKWzLiQ&feature=relmfu
… more about the general settings

Part 5   https://www.youtube.com/watch?v=5XlQIyUPKdU&feature=fvwrel
… about themes, widgets & navigation menus.
(BTW, you can add an SEO plugin to your chosen theme.)

Part 6   https://www.youtube.com/watch?v=5JdhLRUA_e4&feature=fvwrel
… various topics, including adding your own header / banner

Part 7   https://www.youtube.com/watch?v=sPUlrpryU3w&feature=relmfu
… installing & managing plugins and tools, e.g. for backing up your
      content

Part 8   https://www.youtube.com/watch?v=plLKgt5L2rk&feature=fvwrel
… info about creating posts for your blog section, pages, which are static,
     like pages in a book, plus how to set up password-protection.

Part 9   https://www.youtube.com/watch?v=rYN4xlE4Sv8&feature=relmfu
… inserting media (e.g. images), setting up links, & settings for
     comments.