These two ways can help Data Cloud honor a request to be forgotten by a customer. The Consent API allows you to set a consent flag for an individual that prevents further processing of their data and deletes their records from source data streams. The delete from file functionality allows you to upload a file with individual IDs that will be deleted from Data Cloud. References:
https://help.salesforce.com/s/articleView?id=sf.c360_a_data_cloud_consent_api.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.c360_a_data_cloud_delete_from_file.htm&type=5