Great question. You can actually use Shopify Inbox to offer a chat feature on your website. Shopify Inbox lets you manage customer conversations, automate messages, and get insights on which chats convert!
There are also other third-party chat apps you can try out here.
If you're just looking to add a contact us page with the text "Chat with us". You can follow the steps in our help guide.
You can also use chat to close more sales online, check out this blog to learn how.
Let me know if that works for you!
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