How do you enable Change Data Capture on a specific table, and what does that process actually create?

You first enable CDC at the database level using sp_cdc_enable_db, and then enable it for a specific table using sp_cdc_enable_table, which creates a corresponding change table that automatically captures every insert, update, and delete made to the original table going forward, along with the specific columns that changed.

EXEC sys.sp_cdc_enable_table
  @source_schema = N'dbo',
  @source_name = N'Customers',
  @role_name = NULL,
  @supports_net_changes = 1;