How to add product countdown?
Go to Store Admin –> Settings –> Metafields –> Click Products
Click on “Add definition” and add data as below
Namespace and Key: meta.countdown ( Use for other Other Themes )
Namespace and Key: my_fields.countdown (Use for Optimal Theme )
Content type: Date and Time( Select Date )
Now go to your products and Scroll down to “Metafields” and Select Date from Countdown field and click save.