What do the shift keys do and y is there one on each side of the keyboard (answer in 20 words or more)

The shift key is a modifier key on a keyboard, used to type capital letters and other alternate "upper" characters.

The reason there are two shift keys on a computer keyboard is to make it easier to use the Shift function with all keys on the keyboard. For example, it's much easier to use the left Shift key with all the keys on the right side of the keyboard and the right Shift key with all keys on the left side of the keyboard.