the payload request value to be assigned in th true conditi

not just StateFarmTimeCardIDs here we have  OtherTimeCardIDs so anyway to add in this list timeSheetApprovedView??

To assign values when the condition matches, see the code here :

foreach (var Item in timeSheetApprovedView.TimeCards)
{
    if (Item.IsStateFarm == true)
    {
        _LastModifiedDateTC = Global.GetTimecardLastModifiedDate(Item.TimeCardID, (int)InvoiceSourceTypes.TimeCard).GetValueOrDefault();
    }
    else
    {
        _LastModifiedDateTC = Global.GetTimecardLastModifiedDate(Item.TimeCardID, (int)InvoiceSourceTypes.PerHour).GetValueOrDefault();
    }

    if (Item.LastModifiedDate == _LastModifiedDateTC)
    {
        // If the condition matches, you can assign values to the variables here
        StateFarmTimeCardIDs.Add(Item.TimeCardID);
        BaseStateProvinceID = Item.BaseStateProvinceID;
    }
}

In the code above, we first check if the condition Item.LastModifiedDate == _LastModifiedDateTC matches for the current item. If it does, we can then assign the values to the variables StateFarmTimeCardIDs and BaseStateProvinceID as needed.
The code above assumes that StateFarmTimeCardIDs and BaseStateProvinceID have already been declared and initialized earlier in the code. If not, you'll need to add the appropriate declarations before the foreach loop.