How can I properly set up a Twitter Card in my ecommerce platform?

Hey guys, I was trying to share a blog post from my Shopify website on Twitter. But when I pasted a link on the post dashboard, the link couldn’t generate itself into a Twitter Card as the other website does(attached pic #1). I’ve followed the guide from other folks by creating a snippet liquid for twitter card, but it didn’t work. Please advise! Thanks~