New credit card for buying a fridge

Was my decision good?

While buying a fridge I saw this offer that with an SBI credit card I can get 2000 off on the total amount. So I quickly applied for one.

It's yet come.

Only wanted to know if my decision is right also please tell me to use it for maximum benefit.

Only thing I know about credit cards is that I should repay the amount within 50 days.(Which is totally fine by me)

Other than that what all should I know?