Footer Codes

Hi,

I am new to wordpress and websites. I have finished my entire site with changes to lots of the codes and on the last part I seem to have messed up big time.
I was trying to work out how to change the icon for the social media buttons in the footer and iv obviously stuffed up as my entire site will not load now. Is it possible to get the entire code for the footer section and copy and paste it in?
Or how do I fix it?
Thanks