Markup Validation Service – Errors found while checking this document as HTML5!

Hi

my website is http://www.watchnshare.tk and apparently it has some coding errors,
I just got this website from a moderator here but he seems quite busy to reply to my topic only,

Click to view 149 Errors i have in my website

My quetion is: what should I do with these characters that are in red, are they Errors? should I delete them?