One possible reason why a new custom field is not available inthe data stream is that the Salesforce Integration User, which is used to connect to the CRM source, does not have "Read"permissions on that field2. To fix this issue, the administrator needs to grant the appropriate permissions to the Integration User profile or permission set.

The Customer 360 data model is a conceptual model and a canonical model. A conceptual model is a high-level representation of the entities and relationships in a domain of interest, without specifying any implementation details. A canonical model is a common and consistent data model that can be used across different systems and applications. References: [Customer 360 Data Model Overview], [Conceptual Model],
[Canonical Model]

These two statementsare true about using consent API and exercising right to be forgotten. Data deletion requests are reprocessed at regular intervals to ensure that any new data related to the individual is deleted.
Data deletion requests are submitted for individual profiles that represent unique identities in Data Cloud.
References:https://help.salesforce.com/s/articleView?id=sf.c360_a_data_cloud_consent_api.htm&type=5

These are the three data categories to select from when setting up the data source object or schema for data ingestion. Engagement data includes information about howcustomers interact with a brand or product, such as clicks, views, likes, etc. Order data includes information about transactions or purchases made by customers, such as order ID, amount, date, etc. Profile data includes information about customers' attributes or preferences, such as name, email, gender, etc. References: [Data Categories]

This feature can help Northern Trail Outfitters calculate each customer's lifetime value (LTV) and create breakdowns of the revenue sourced by different channels. Streaming data transformations allow you to transform and enrich streaming data from different sources using formulas and operators. References:
https://help.salesforce.com/s/articleView?id=sf.c360_a_data_cloud_streaming_data_transform.htm&type=5