How to activate Smart Dual SIM in Samsung Galaxy J2-2016(SM-J210F)?

Smart Dual SIM enables call waiting on both the SIM cards. It even enables the call forwarding on both the numbers. So, if one of the numbers is out of reach, the incoming calls will be forwarded to other number.  

Navigate to Apps → Settings → More connection settings → SIM card manager → Smart dual SIM → Enter both SIM card Numbers → Next → Finish → Ok

Pictorial representation to activate Smart Dual SIM is as follows: 

a). Tap on Apps icon from the Home screen.

b). Drag the Screen upwards to access more apps.

c). Tap on Settings icon.

d). Tap on More connection settings.

e). Select and tap on SIM card manager.

f). Tap on Smart dual SIM option.

g). Enter the Number of both the SIM cards.

h). Tap on Next.

i). Tap on Finish.

j). It will take some time to Activate.

k). Tap on Ok.