Using Excel, make a regression: Y(stock return) = constant + Beta*X(Index returns) + Error terms

Monthly	Adj	close
Date	KLCI	Stock price
Nov-20	1,562.71	10.08
Oct-20	1,466.89	9.54
Sep-20	1,504.82	10.5
Aug-20	1,525.21	10.86
Jul-20	1,603.75	11.44
Jun-20	1,500.97	11.62
May-20	1,473.25	11.26
Apr-20	1,407.78	12.24
Mar-20	1,350.89	12.02
Feb-20	1,482.64	12.1
Jan-20	1,531.06	12.46
Dec-19	1,588.76	13.26
Nov-19	1,561.74	13.16