Q: When we press = sign, we can move immediately to the end of a chart.    What key do we press to go to the BEGINNING of a chart?

A: Hold down the Shift key when you press the   =   key. Also the mouse click equivalent of the keyboard for both actions is to click the Reset button on the charts panel  for the  =  key,  or hold down the Shift key when you click on the Reset button to jump to the beginning.  Shift is a modifier for both.