help, cannot add social media icons to navbar…!

hi
my blog is https://www.huus57.com, using a twenty twelve child theme. i’d like to move the social media widgets i created (see sidebar) into the sidebar, but so far i’ve had no luck, nothing i do shows up in the navigation bar. i tried this advice and another tutorial it referred to: https://theedgecode.com/add-images-to-wordpress-menu-links/

however, i cannot get anything in the menu that says custom link or page or similar. i get page (only lets me choose between about and home), links (url and link title), categories etc.

i don’t like the way it looks at the moment, if anything the icons should be next to eachother, not in a vertical line.

please help ?? thank you!
barbara