You can easily add your favorite live chat application to your site:
1) Create and Copy the embed code snippet from your live chat application site. Please refer any questions about that to your live chat support.
2) Paste the code snippet into your site's topic: 0-template-live-chat on the HTML tab.
3) BE SURE to overwrite the default HTML code the topic may contain, as it is already in your responsive template view file. It will look like this:
4) Your copied code snippet will look something like this (example):
5) Save the Topic and make sure it is Published.
6) Refresh Store
7) Refresh your storefront page to verify it is displaying (Ctrl+F5).