Facebook links not showing correctly

Recently when I link from facebook to one of my articles, the intro text is a string of code rather than the first few lines of the article.

Then I have noticed on my site this:

” />

Above my header on every page. The string of code on the facebook link also starts with ” /> . I suspect it’s something to do with my CSS but I am not sure.

You can view the symbols at https://www.liamfoneill.com
I would love to be able to fix this. I have tried changing to a different WP them but it is still not working.