First, duplicate the theme file you are going to use. If your theme has problems after modifying the code, you can revert to using the backed up version.
Click the “Actions ”,and select “Edit Code” in the dropdown list.
Click on "Add a new section" option below the "Sections" folder.
Name the section file:
This will generate a default section file as shown below.
After purchase, a link to download the file will be sent to your email.
Now the section was installed, you can leave the code editor page.
Now go back to the Shopify admin page.
Open: Online Store → Themes → Click the “Customize” button next to the “Actions”.
Select the newly created section.
At this Customization page, click on "Add section" above the "footer" in left side bar.
Choose the page you want to customize and add the section to, click on the “Add section” button at the bottom of the left sidebar, above the "footer" option in this theme.
Select the section you just created in the shown list.
If you have problems with the installation, please feel free to contact us at: firstname.lastname@example.org