Hi @Hnin_Sandar_Lwin,
A row in the daily profile table is a signature of how a street varies in speed throughout the day. It is possible for multiple streets to have the same profile if they vary in speed identically to each other. It is also possible for a street to have the same profile over multiple days (for example, the variation in the speeds on Tuesdays is the same as the variation in the speeds on Wednesdays).
The street daily profile table indicates which streets are matched to which profiles for each day of the week.
See the help topic at https://desktop.arcgis.com/en/arcmap/latest/extensions/network-analyst/traffic-historical-10-1-and-l... for more information on both of these tables.
You can purchase historical traffic data from most street data vendors, such as TomTom and HERE -- the SanFrancisco.gdb tutorial dataset is based on data from TomTom, whereas the SanDiego.gdb tutorial dataset is based on data from HERE.
More than likely, the historical traffic data you get from a vendor is in the vendor's proprietary format, and isn't in the format of the daily profiles and street daily profiles tables used by the network dataset. How you transform the vendor's data into the tables for use in the network dataset will vary by vendor. You can look at the documentation provided by your vendor to understand the content of their data, and then compare it with the documentation for the network dataset's historical traffic to determine what steps you will need to transform the vendor's data into the tables used for the network dataset.
Please let us know if you have any further questions. Thanks!
Alan