The way to know whether the credit card given by your boyfriend can be used is to check the card type, check the expiration date, and call the customer service number.

1. Check the card type: Credit cards usually come from different brands such as Visa, Mastercard, American Express, etc. You can check the logo on the card to determine.

2. Check the expiration date: Credit cards have an expiration date, which is usually marked on the upper right corner of the front of the card or the lower left corner of the back to ensure that the card has not expired.

3. Call the customer service number: You can call the customer service number on the back of the card and ask the customer service staff whether the card has been activated and available, and whether there are any restrictions or loss reports.