When you first start Firefox, click the home button or create a new window you're greeted with the default home page. This page contains a handy default engine web search and quick links to downloads, bookmarks, history, add-ons, sync and settings. Also, if you had tabs open the last time you used Firefox you can restore them from the home page with a single click.
The default Firefox setting is to show you the Firefox home page when you start Firefox, click the home button or open a new window.
If you don't see this page when you start Firefox, click the home button or open a new window you can restore the default setting like this:
When you open Firefox or create a new window you should see the default home page with the following buttons at the bottom of the page:
If you had tabs and windows open when you closed Firefox, the default Firefox home page will have a Restore Previous Session button on it. To get your tabs and windows back, just click it.