In Date(year,month,day) function, all need to be number, what if I have month
in letter, how can I use date function?

I've tried a different way by using if, nested function only allow 7 or 8 of
them, so I can't nest the function all the way to December.
If(A1=January,01,if(A1=February,02......and so on)

Anyone have any suggestions on how to do this?

Thanks,
GU