index extension page?

Where in AllProWebTools can I find what you have our index extension page set as?

I was unable to find any information about "index extension page"

hmm maybe I worded it wrong....we are looking for what the extension is for the index page (it's usually index.php, index.html, home.php, or a variation of such) but we can't find out where to find this info in the AllProWebTools console for our website?