Beginner Question 1: Editing Homepage

Hi all, I finally got wordpress working on my site (geneparkmusic.com). However, I’m having trouble getting information on how to edit the homepage. If I get the source code via Firefox, I can see the text I want to edit, but where is the file in WordPress so I can actually do the editing (change text, like the “proudly powered by” text at the bottom, or add pictures to the header).

Thanks