How to remove text/widget area from a page?

I am a total beginner in Wordpress... I am trying to create a homepage that would house only a full background image, menu on the top and maybe a little bit of text on the top of the background image (or maybe a button linked to some content of the site). I am struggling with getting rid of the text area (the area is blank when the page is published and that messes up the whole visual aspect of the page). Also, I am wondering is that possible to assign a different background image to each and every page? I am using theme named "bento". The name of the page is www.sirdsmeditacija.lv There are some other things on the page that should be changed but this is the main concern at the moment.