Yes SplitRecord is what you should use.
Attached is a flow definition as an example.

Note that I had to rename the file with a "txt" extension once you download it rename it to a .json extension

You can then drag a processor group and it gives you an option to upload the flow definition.

That example generates a file with 102 records and on SlitRecord we use a JsontTreeReader that will split by 3 records and writes the flowfiles out, In this case per 3 per flowFile generating 34 FlowFiles.

1-2 / 3 = 34

In your case and based on your screenshot I would change split count to be 1500000 ( or another number based on your needs )