Hello Narendra and welcome to the Community!
There are multiple tools available to convert a CSV file to a JSON format. Unfortunately, we cannot recommend one tool, but a quick google search will show multiple options.
If security is a concern then you’ll most likely want to avoid freeware or online tools to do such a conversation. A solution I’ve done in the past is to create a script to manage these types of conversions.
I hope this provides some guidance on how to move forward and assists with your goal.
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