@Rahul Bahadur​ there a few ways to pass values between tasks in a job:

1. [new] we are previewing a new API for setting and getting small values (e.g. a few KB or less) between tasks in a job.
2. Write the value to a table in one task and read it from another task

So it appears you are trying to use No. 1. Please email me at bilal dot aslam at databricks dot com and I will get you enrolled in the preview.