I purchased a smart watch recently. But how to activate sim card for smartwatch.

This is the product link: https://www.helenwatch.com/products/men-smartwatch-for-apple-iphone-samsung-android

I think some higher-end smartwatches use eSIM technology? A "virtual" "universal" SIM HW is embedded within the smartwatch, which, assuming your mobile provider supports the embedded technology, can be re-programmed to work with your provider/plan.

 

Otherwise, you'll have to use Bluetooth to communicate with a mobile phone (which has a SIM), for mobile telephony services (voice calls), and internet access (over and above embedded WiFi).

 

I think that's what that watch seems to require? 

 

What are you hoping to be able to do re: SIM?