Themes and templates confusion

OK so here is my site http://www.larascakes.co.uk. I am obviously in very early stages and really new to all of this, not got my head around the coding yet. I want to set up a home page which basically just has the header and perhaps the word welcome on it. I have read about changing templates but I can’t I am using the theme buttecream and when I go to that there are lots of templates but when I try to select one (i.e. go to the templates drop down in page editing, I don’t get any options other than default template or gallery template.

I think I may be in very over my head here haha. Any advice gratefully received.

Thanks in advance