Custom theme header warning error

I need some help with the work I’m doing on my custom wordpress theme. On my admin page for WordPress I’m getting this error at the very top of the page: Warning: Cannot modify header information – headers already sent by (output started at /home/link01/public_html/blog/wp-content/themes/TEAtheme/functions.php:8) in /home/link01/public_html/blog/wp-includes/functions.php on line 851

Warning: Cannot modify header information – headers already sent by (output started at /home/link01/public_html/blog/wp-content/themes/TEAtheme/functions.php:8) in /home/link01/public_html/blog/wp-includes/functions.php on line 852

I have no idea what I’ve done to set off this error. My header’s file code consists of:

[code moderated - this is not the header that is referred to in the error message]

To reach the wordpress site just go to https://www.theentertainmentart.info/blog . I could really use the help on the account that it no longer allows me to post stuff, and I just got the theme around the area where I want it to be.

Also, when you post comments you get this error on my site: Warning: Cannot modify header information - headers already sent by (output started at /home/link01/public_html/blog/wp-content/themes/TEAtheme/functions.php:8) in /home/link01/public_html/blog/wp-includes/pluggable.php on line 897

There's a specific hierarchy within wordpress themes that it reads from. I obviously am either missing something or put something out of place. Is there any way anyone could help? The actual blog is at theentertainmentart.info/blog