I can not add card to apple wallet. I pressed the plus sign it shows a dialogue box which has two option lean more and other…what should i do ?

Click on "Learn More". That usually explains a bit more about the issue.

That message usually comes up, when your Phone is set to a region that does not yet support Apple Pay. What is the region set for your iPhone in Settings->General->Language & Region->Region.

And is it one of the countries and regions listed in the following link as supporting Apple Pay: link-> Countries and regions that support Apple Pay - Apple Support

If it's not a supported country, then you cannot add actual credit or debit cards to wallet yet. Only passes, tickets and gift cards from an App, email ir QR code.