To place a Facebook (FB) Like button on the Home/Main page of your website (or any page with a text box), 

• first obtain and copy (Ctrl/C) the iFrame code from FB for the widget (aka badge)

Follow the steps on this FB page to obtain the iFrame code:
Like Button for the Web which includes these steps:

For Like Button Configurator 

• insert your website url in the URL to Like field
• adjust settings like the width of your like button. 
• click Get Code button

• click IFrame (at top)
• copy the code (ctrl/C)

To add the code to your main page:

• login to FASO account Control Panel
• click Your Site's Home Page (left column near top)
• for Main Page Text area, click HTML (right-hand icon above the text box)

• new screen pops up
• place your cursor where you want the button to go (top or bottom of existing code)
• paste (Ctrl/V) the code from Facebook
• click Update
  you should now see your widget
• click Save Changes

Also see this FAQ:
Add Sharing Bar, Like Buttons or Widget