Using Dateadd function adding day,month,year in date

select

dateadd(datepart,number,date)

eg-

select

DATEADD(month, 3, getdate()) 

Datepart

|Abbreviations

year| yy,yyyy 

quarter| qq,q 

month| mm,m 

dayofyear| dy,y 

day| dd,d 

week| wk,ww 

weekday| dw, w 

hour| hh

minute| mi,n 

second| ss, s