can't figure out how to install mailwizz

I open up the install and all I see is a bunch of .php files.
You have to open the install via the browser, you have to access the url of your install folder, something like and then the installer will guide you through the whole process.
If you done that and you see the files list in your browser, then it means your web server doesn't execute PHP, which you should talk to your hosting about
Why is this so difficult?
Mailwizz installs the same way any web application installs, be it wordpress, drupal, joomla, xenforo, whatever. There's nothing different, it's just the way things work.

on top of that I'm trying to log into the site and it says my email is invalid.
You'll get login there after you install the app, you'll receive an email ;)
@indiemusicpeople - then that's a server issue, nothing to do with mailwizz :-s
Remove the redirect and you will be fine, you will be able to access the installer.
Contact your hosting if unsure, they'll know what to do.