What credit cards should I own (for fresh grad)?

Hello. I would like to know what credit card I should apply for. I'm looking for a card that earns good cashback for shopping, online spending and travel (foreign currency expenditure or travel)? Not sure if i should apply different cards for these expenses or is there a card that allows me to fully maximise the cashback (or even rewards points or miles) from these expenditures? Thank you!! :)