It depends on the eCommerce platform that you are using, there are lots of Chat Support plugins that you can easily integrate in your blog or site however, most of them has a monthly or annual subscriptions fees.
If you want a free chat support, I recommend MEBIW it enables one-on-one chat assistance in real-time directly from your website.Free open source & easy to install inside your site whether you are using wordpress.org, blogger, prestashop, magento and other platforms that supports HMTL codes.
- Real-time chat (without page refresh)
- Unlimited operators, chats, and users
- Unlimited departments (groups of operators)
- Priority queue of visitors
- Localized to 10+ languages, unicode support
- Runs on your server and domain
- Easy-to-modify source code
- No leave a message feature
- No Call, only chat
- Only four choices of buttons