How to take backups on a defined directory instead of creating sub-directories
You just need to change the Directory parameter in the Ola Hellengren script. Go to the job, click the Step --> Edit-->@Directory = 'C:\Backup',

This will be enough.

Adding to your particular requirement, I went into the Store proc and was able to figure out. This took me some time so apologies for that. Please mark this as answer once you are able to complete your task.

Below are the steps to get your required directory :


For getting all backups to just one location, you will need to remove few parameters from the store proc [dbo].[DatabaseBackup]. There will be this part where you set variebles( Look for the comments) -- Set variables
Go ahead and look for the below part :



  SELECT ROW_NUMBER() OVER (ORDER BY ID), DirectoryPath + CASE WHEN
  RIGHT(DirectoryPath,1) = @DirectorySeparator THEN '' ELSE
  @DirectorySeparator END + CASE WHEN @CurrentAvailabilityGroup IS NOT
  NULL THEN @Cluster + '$' + @CurrentAvailabilityGroup ELSE
  REPLACE(CAST(SERVERPROPERTY('servername') AS nvarchar(max)),'\','$')
  END + @DirectorySeparator + @CurrentDatabaseNameFS +
  @DirectorySeparator + UPPER(@CurrentBackupType) + CASE WHEN
  @ReadWriteFileGroups = 'Y' THEN '_PARTIAL' ELSE '' END + CASE WHEN
  @CopyOnly = 'Y' THEN '_COPY_ONLY' ELSE '' END, Mirror, ROW_NUMBER()
  OVER (PARTITION BY Mirror ORDER BY ID ASC), 0, 0   FROM @Directories
  ORDER BY ID ASC



Now you need to remove the parameters : @CurrentDatabaseNameFS and UPPER(@CurrentBackupType). This will create all your backups to a single location as below




Go through each of the available parameters in Ola hellengren scripts. Ola Hellengren