Does confluent kafka provide an api for streaming, grouping and aggregation in python language?
There's no such thing as "Confluent Kafka". Confluent Platform is a distribution of Apache Kafka®, along with other components such as the Schema Registry, KSQL, etc.
Apache Kafka includes the Kafka Streams API, which is only available for Java and Scala.
Options that you have for stream processing include:
Disclaimer: I work for Confluent.