Firstly, you need to make sure you are part of all the project the user is assigned in. Further, you can follow the below steps:-
1. Navigate to the task list page in the tool.
2. Select ‘All’ from project drop-down.
3. Click on the filter icon in the top-right corner of the page.
4. Select ‘Assigned to’ and choose the name of the user. You will get all the details task along with project details for the task list view.