Am not able to add wallet why

See the following Apple articles:

Countries and regions that support Apple Pay

Countries and regions that support Apple Pay - Apple Support (EG)

Apple Pay participating banks in Africa, Europe, and the Middle East

Apple Pay participating banks in Africa, Europe, and the Middle East - Apple Support

If you can't add a card to Apple Wallet to use with Apple Pay

If you can't add a card to Apple Wallet to use with Apple Pay - Apple Support

About billing for Apple subscriptions and media products in India

About billing for Apple subscriptions and media products in India - Apple Support

India

•           Apple ID balance (from adding funds)

•           Net Banking (adding funds only)

•           UPI (adding funds only)

You can use / pay with your Apple ID balance, see: Add money to your Apple ID balance

Add money to your Apple ID balance - Apple Support (IN)