You can fetch an entity into a datatable, by using the static (shared) method GetMultiAsDataTable() of the entity collection of the entity.
The order of the fields in an entity is also the same as in the table. You can also fetch an entity and add columns to a datatable and read the entity.Fields object from front to back. You can determine the various table information using the entity.Fields[index]. properties, like entity.Fields[index].SourceColumnName for the tablefield name