You have unlimited customization of your website. There are no limits to the number of updates you can publish or schedule.
To make a change to a page on your website click on Website on the top navigation bar, then click Website Pages. Then, click on the page you would like to work with.
Click on the pencil icon next to your Current Page or if you want to work on a draft you have not yet published click the pencil icon next to the appropriate draft.