upload troubleshooting

Hi, guys, I get a new arduino UNO R3 board from ELEGOO, but when charging a small program to test it I got an error message like this:

Arduino: 1.8.4 (Windows 10), Board: "Arduino/Genuino Uno"

Sketch uses 928 bytes (2%) of program storage space. Maximum is 32256 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.
avrdude: ser_open(): can't open device "\\.\COM1": The system cannot find the file specified.


Problem uploading to board.  See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

I will very appreciate it if someone can help me solve this issue. thanks

Select the COM port of your Uno from the Tools > Port menu.

If that menu is grayed out or the port of your Uno is not shown on the menu then you may need to install the driver for your Uno or you may be using a damaged/charge-only USB cable.

Thank you very much. it work