Location of json data file and yml

I would like to specify in the yml file where the json data file is located.
It is the file that I would like the elasticsearch to read.
I have set in the yml
path.data: /etc/elasticsearch/data
and elasticsearch seems to run without a problem
There in /etc/elasticsearch/data/elasticsearch I have put the folder drug that contains the json file.
Elasticsearch seems that has created one more folder nodes.
image

The question is if the path.data refers from where the elasticsearch reads the data or where it writes its data.
If path.data refers to the destination where data is written where can I specify the location from where elasticsearch reads its data? The data that should be searched

The data are from OpenFDA and there is a json file which contains all the urls from where I can download the data.
https://api.fda.gov/download.json

https://open.fda.gov/apis/downloads/

I am a little bit confused with how I can a search in these data and the first question is where the data should be located and if this should be done via elasticsearch command