You are trying to find simplistic answers to a relatively complex subject. At the very least you should go to a music store and purchase a beginning piano book or a beginning music book for children or adults and study the basics of how music is notated.

By way of example, I do not think you would be successful at writing a computer program to display Chinese calligraphy on a computer screen if you were completely ignorant of how brush strokes are used in Chinese characters, and you thought you could accomplish the text without learning the basics of Chinese brush strokes.

Read a book or consult with a piano teacher.