How to make the home page ('house'-icon) editable?

Hello all,

I might have a simple problem, but i cannot find the solution so far. For one of my hosting customers I installed WordPress and installed the free ‘application’ theme. I can add pages and then I’m instandly able to edit them too. But in the theme, there is a little ‘house’-icon; the icon to go to the homepage. But I cannot find anywhere how to edit that specific page. In the list of pages, the homepage is not included, so the only way to edit the homepage, is to download the index.php via FTP, edit it and upload it again. But I guess that’s not the way it supposed to be?

What I want to do is to make the homepage editable. That’s main goal number one, but I also want the ‘house’-icon to stay intact and still be the homepage. Is there a way to do this?

Thanks in advance.