crud operations belong to? code example

Example: To give permission to the specific user for the CRUD operation in the database at a time

USE OnlineRestaurant1
GO
EXEC sp_addrolemember N'db_datawriter', N'RAHBARINFOTECH\LOVE'
GO
EXEC sp_addrolemember N'db_datareader', N'RAHBARINFOTECH\LOVE'
GO