MSSQL 2014 Combine Bulk Insert and Update using Stored Procedure

Transact-SQL
1 
From the table above, I want to perform Bulk Insert and Bulk update using just one stored procedure. If it is update it will take the field **score_data** as parameter. Please how do I perform this bulk insert and update.  Table name is 
CREATE TABLE [Student].[exam_score](
	[exam_score_id] [int] IDENTITY(1,1) NOT NULL,
	[department_id] [int] NOT NULL,
	[student_profile_id] [int] NOT NULL,
	[exam_score_type] [int] NOT NULL,
	[academic_level_id] [int] NOT NULL,
	[academic_semester_id] [int] NOT NULL,
	[academic_year_id] [int] NOT NULL,
	[created_date] [datetime] NOT NULL,
	[created_by] [nvarchar](128) NOT NULL,
	[updated_by] [nvarchar](128) NOT NULL,
	[updated_date] [datetime] NOT NULL,
	[state_id] [int] NOT NULL,
	[study_centre_id] [int] NOT NULL,
	[programme_id] [int] NOT NULL,
	[score_data] [varchar](max) NOT NULL)
Thanks