Hi @Yashpal Chepuri ,
Welcome to the Atlassian Community!
The below documentation page for Jira Server explains how to import from TFS into Jira:
The instructions in the above page apply to Cloud as well as long as you then follow the instructions in the Importing data from CSV page for Cloud, or you choose any of the listed add-ons that is also available for Cloud.
You may also want to review the below links for more details and/or alternatives:
For the rest, regarding the integration with Git, please see if below links help, or provide more details on what you are thinking to use (Bitbucket, Github, etc):
I hope this helps.
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