How to update portal report?

Hi,

Review Appian Documentation to know how to create and configure Appian task and process report.

Process Reports: https://docs.appian.com/suite/help/22.1/Process_Reports.html

Task Reports: https://docs.appian.com/suite/help/22.1/Task_Report_Tutorial.html#create-and-view-the-task-report

So my task report is coming from multiple process models and for one of the process I want to update those shown values. So I am not sure whether we can update task report or not .

If you're saying that you want to update the value at the source from the report, then that is not possible. 
Reports are only used to get the values. Tasks are generated by the task engines.

Is there any way I can pass value to the grid generated using task report??

No, as that's not what they're for.   If you could tell us a bit more detail as far as what you're trying to do and why (or, what you're trying to accomplish over-all in a big picture sense), we would probably be able to give you some more useful feedback / alternative suggestions.

No, as that's not what they're for.   If you could tell us a bit more detail as far as what you're trying to do and why (or, what you're trying to accomplish over-all in a big picture sense), we would probably be able to give you some more useful feedback / alternative suggestions.