Try this:
CREATE PROCEDURE AddNewUserProc
@NricNo VarChar(50),
@donorNric VarChar(50),
@donorName VarChar(50),
@donorAddress VarChar(250),
@donorPostalCode VarChar(50),
@donorContactNo VarChar(50),
@donorType int,
@donorOrganizationName VarChar(250)
AS
IF NOT EXISTS (SELECT NricNo FROM Donor WHERE NricNo = @NricNo)
BEGIN
INSERT INTO Donor(NricNo, Name, Address, PostalCode, ContactNo, Type,OrganizationName) VALUES(@NricNo, @donorNric , @donorName , @donorAddress, @donorPostalCode, @donorContactNo, @donorType, @donorOrganizationName)
END
Don't use
{ }
brackets to create your procedure, but use commas to seperate the arguments.