The years on your sample workbook are all 2021. Did you mean them to be different?
In any event, the way to solve the problem is to build a table showing the cash flows on a month by month basis for the entire duration of the opportunity. NPV, IRR and PV require equal time intervals. Make sure that the initial investment has a different sign than the potential returns. And because you are tabulating the cash flows on a monthly basis, use 10%/12 as the interest rate.
Sorry I sent you the wrong excel file. Here it is. NPV IRR PV.xlsx
Microsoft Excel
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In any event, the way to solve the problem is to build a table showing the cash flows on a month by month basis for the entire duration of the opportunity. NPV, IRR and PV require equal time intervals. Make sure that the initial investment has a different sign than the potential returns. And because you are tabulating the cash flows on a monthly basis, use 10%/12 as the interest rate.