There is a 'Work' Field.
To include this in a Gantt Chart view, right click on the header row of the task list, choose "Insert Column" and select the "Work" field name.
This will show you the hours/days - depending on the setting in Tools/Options/Schedule screen for "Work is entered in..." field - for that task.
e.g. If you add a resource the total work will probably double or the duration will halve (depending on other dependancies and task)
MS project does not give you total effort for the project; it is scheduling and tracking tool. You need to you estimation process to calculate total number of Man days for the project. I suggest following FP or WBS approach. Saving Changes...
No but if we have entered all the estimates against functional points in MS project and see the work column that shows the total effort in hours or days (as per the settings), with resource assigned , does it not mean we can calculate the man days from the work column? Saving Changes...