Home Page Questions

For Q2 – I am using the hamburger nav but as you can see this screen shot – the sub-section posts are very faint, grey, how can change the font colour so that is more visible?

You can do that by using the below CSS code as described above.

#page .navbar-default .navbar-nav .open .dropdown-menu > li > a {
    color: #636467;
}
For Q3 – Is there any recommended reading I can do to learn how to change this code?

You can refer the solution posted in the following topic.

https://colorlibsupport.com/t/footer-links/

For Q4 – I have downloaded the GetSocial plugin and can use it and edit the metadata for the other posts and pages but can’t do the Home page since it’s not a physical page… How can I influence this page’s social meta data?

Talk with the plugin developer or try using this plugin Yoast SEO – WordPress plugin | WordPress.org