You can find your debit credit card's card number and CVV on your physical debit card.
But you have them displayed in the app as well. To access this information, click on the image of the desired debit card under Cards and then click on "Showcard details." You then have to enter your PIN and another 6-digit PIN that you will receive via SMS before you can see your credit card details
You can easily see the IBAN of your account by clicking on your profile in the app and then on account data. Please note that your IBAN starts with LI and only has 20 digits instead of 22 digits. Your foreign currency accounts do not have their own IBANs as they are sub-accounts. But you can also see their account number here.