Why Azure SQL Server table used space is too high?
Using bigger data types
These columns in dbo.Table1 are varchar(50):

[ID]
[C_ID]

In dbo.Table2, they are nvarchar(32) and nvarchar(64).
The added &quot;n&quot; makes each character take up twice as much space as the varchar version.  It's possible the same thing is going on with the FK column and P_COUNT, but I don't see those defined on the original table, so I can't confirm.
There are a couple of datetime2(7) columns changed to datetime, but these have the same storage cost, so that shouldn't make a difference.
If you get your data types back to what they were in the original table, you should see a pretty big reduction in space used.  Note that you will need to REBUILD the clustered index (or just drop and reload the table) after making the data types changes.
Fragmentation?
It's possible that fragmentation is contributing to the additional size of dbo.Table2.  If the size is still significantly different after fixing the data types and recreating the table, you could try loading the table with ORDER BY [ID] OPTION (MAXDOP 1) to limit fragmentation in the target table.