Excel help to create IRR and MOIC results within an existing cashflow

Description of excel work: I have an existing excel file which provides a cashflow model for a real estate project involving land acquisition and subsequent land sales. I have 3 tasks I would like support on:

1. Calculate the IRR of the cashflow - I can't get this working properly from the data and dates I have inputted;
2. Calculate the MOIC - this is an important metric which I would like to display alongside the IRR;
3. In one cell I have identified the peak cashflow, in the next cell I'd like some way of automatically presenting what date this peak cashflow event occurs.

I would be grateful for someone who could support me quickly on these three tasks and provide a short explanation as to how they were addressed.

I would prefer not to share the excel file until it I have appointed someone, but I will say that the spreadsheet is very simple with a relatively small amount of data.

Thank you.
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