Storing historical data

I am planing to use the influxdb in grafana v4.2, May i know how long the historical data will be stored in it ?

That depends on your InfluxDB settings & database retention policy

I just created a datasource using influx db , but I am unable to understand the influx db settings for more storage … Can you let us know in detail, also can you provide a sample influxdb settings to store a huge historical data