Read the page below: How-to migrate Backlog Items from TFS to DevOps
Go to TFS and find your project.
Click on Work > Queries > New > New Query
On Editor, add a filter:
Work Item Type
User Story, Bug
State
To Do,In Progress,Active,New,Pre-Acceptance,User-Acceptance
Save query as
Open a new Excel file
General
Content
Integrations
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