Hi i have a question I'm playing some wargame challenge i have stuck i a web challenge

i knew how to solve t but i can't find the request i need to return to a portion of a page >>>>>> [HTML_REMOVED]You can't get the flag[HTML_REMOVED] so i need to send the request with crlf injection

my question is what is HTTP header that allows you to return a portion of a page and also it's a requests for comments