Whenever you create the website you have multiple aspects of your home page to take a look at. i.e Slider section, Trending Section, etc, Social network URLs, Optin Form Adsense Codes, etc.
To Update, these settings AdSense lab have an option in the left sidebar under Manage Websites which Called as "HomePage Settings", Please Refer Below Screenshot.
Once Homepage Listing page is loaded, click on add homepage setting button at top right
The Form will load, the form have multiple sections
Once all settings added, Save the forms and visit your website to check if everything is working fine.
Please feel free to reach to us if you need any help