OCPP configurations describe the key value pairs received of the charging stations during GetConfiguration requests. Those values are defined by the stations and might differ from between models and firmware versions. Those values are the stored values in the be.ENERGISED system. If you want to refresh those values, you need to call the remote command GetConfiguration.
OCPP Configurations can only be read in the context of a station /cpoapi/v1/charging_stations/<station_uuid>/ocpp_configurations/ or with a concrete id of a configuration /cpoapi/v1/<station_uuid>/ocpp_configurations/<config_id>/.
The list will be in the format of the offset pagination. The configuration can be filtered with keyContains and Key which will filter out values which contain the set value in its key.