Open Settings → General → About. Check Model Name, then tap Model Number to see the A-number. For example, iPad Pro 11-inch 2nd Gen (2020) uses A2228, A2068, A2230 or A2231. iPad 11th Gen / A16 is a different model.
USB-C cables for compatible laptops. These are everyday USB-C cables, not Thunderbolt or video cables. For laptop charging, check the required power and use a suitable power adapter; these cables support up to 60W.