you may have to delete your index.html page and start again with what page has the template you don't want

you need to decide how you fully want your site and what editor you are going to use before you start MESSING around with it

The simplest way is to design whatever you want, test it in your own browser, and upload it using File Manager or FTP. You can also just cut paste the entire HTML of your page at the index.html or other pages. To do so, go to "edit HTML", and just highlight or delete the entire content of the edit box, place new HTML, and save it.