Newbie needs help!

I copied this error message: What do I do?

Arduino: 1.6.4 (Mac OS X), Board: "Arduino Uno"

Sketch uses 1,208 bytes (3%) of program storage space. Maximum is 32,256 bytes.
Global variables use 11 bytes (0%) of dynamic memory, leaving 2,037 bytes for local variables. Maximum is 2,048 bytes.
avrdude: ser_open(): can't open device "COM1": No such file or directory
ioctl("TIOCMGET"): Inappropriate ioctl for device
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"
enabled in File > Preferences.

And there is an orange light blinking next to L What does that mean?

The Mac doesn't use the name "COM1" but that appears to be the default when you don't select a serial port under Tools->Ports.