The amount of capital gain main residence exemption should only be reported at Item 18 in HandiTax:
Item 18 - Capital gains in the Main form, Code I lets the Australia Taxation Office know that you are reporting the Main residence exemption (Subdivision 118-B).
As this income is exempt, the income information should not be entered in the Capital Gains Worksheet.
If you have further queries on what data to enter at these items, please contact the ATO.