If you are just getting started with Go, or have may have just forgotten, here is a quick reference for building a basic go program.
First create the directory and file
mkdir HelloWorldGo
cd HelloWorldGo
touch main.go
Then, use the following Go code.
package main
import "fmt"
func main() {
fmt.Println("Hello World!")
}
And run the code with the following command.
go run main.go