Please help fix hack..index.html

Hello,

I’m still trying to fix the hack on my site. In my file manager at my hosting provider, there is a file index.html which, when I view, shows an image of the hack on my site (see thelimegreenscream.com)

I uploaded a new wordpress, but when I looked in the wordpress folder there is no index.html. There is only index.php

Does anyone know where this index.html is an important file for wordpress?

Do you think the file was only placed there by the hacker? i.e. can I just delete index.html and not replace it with anything?