You may include a link to a webpage in a form. To have this webpage open in a new browser tab (as opposed to "on top of" the open form), follow these steps:
Enter the website into the Description field of the form.
Highlight the text, and click the link icon to edit it.
The "display text" is what you want the form respondent to see; the URL is the webpage that needs to open.
Click the HTML editor (#2 below):
The text will look like this:
<a href="http://www.soniabyqsr.com/">Sonia website</a>
Just modify it to include a target, and it will look like this:
<a href="http://www.soniabyqsr.com" target="_blank">Sonia website</a>