my site is redirecting

My site is redirecting to some other sites, My host said they detected malware here:
public_html/wp-feedpost.php
public_html/wp-feedpage.php
public_html/wp-feedcategory.php

Can anyone help me as to what I need to do? They also told me my wordpress and plugins and php are outdated but not to do anything if I do not know what I am doing. can someone help as to what I need to do?

Thank you
Denise

The page I need help with: [log in to see the link]