When you enter edit mode the first tab opened is the 'Layout' tab and the Layout tab's tool bar is showing on the screen. Inside that tool bar there are tools for editing the text of the text & image item.
To reach the layout bar, you need to click the edit icon of the text and image item. There are 13 different layouts available to use to design your site.
To add a text & image widget to your website simply drag & drop it , to learn how click here.
The image above is one example of a text & image widget. The text & image widget comes in many different shapes. That way you can pick the image & text widget that most fits your needs.