What kind of calling card do I need to buy to travel to America?

Subcase: 1. Whether it is necessary to purchase an international roaming card or an American SIM card (the international roaming fee is: 1 yuan per minute for answering and calling back in China, 1 yuan for sending short messages in China, and free for receiving short messages);

2. You can buy prepaid SIM cards in America. Generally, it contains a SIM card with some prepaid phone bills or limited time packages, which can be used after the card is activated. After the end of the call, the recharge card and the call usually have their own validity period, ranging from 1 month to 3 months after activation:

3. You can choose American national carriers.