Hi @Shubhi Khandelwal ,
Welcome to the community!
Please read this documentation https://support.atlassian.com/jira-cloud-administration/docs/import-data-from-trello/
I don't think so that boards/data are gonna be deleted after import to jira!
Importing means it will copy the data or sync among them!
check out these for more information
Hello Community! My name is Brittany Joiner and I am a Trello enthusiast and Atlassian Community Leader. I'll be sharing with you a series of videos with my top tips on how to best use Trello...
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