In order to check if your board is connected to the Arduino IDE, you can go to Tools -> Port. It should show all the available COM ports.
Now, you can disconnect your board. If one COM port disappears, then you can be sure that your board was connected and detected by the Arduino IDE.
This practice also helps you identify the correct COM port corresponding to your board, when multiple COM ports are available. In case your board is not getting detected, there maybe some issues with the USB Drivers. On Windows, you can open Device Manager, and open Ports (COM and LPT). If there is an issue with detecting your board, it is indicated there. You can right-click on the port and select 'Update driver'
If your board does not get detected in the Device Manager as well, it may be a good idea to change the USB port to which you are connecting your board.