I need help on filling out information for Annualized Income Method which I have to calculate amounts for 3/31, 5/31, and 8/31. How do calculate AGI, deduct, and gains?

The Annualized Method determines your estimated tax liability as your income accumulates throughout the year instead of dividing your entire year’s estimated tax liability by four as if your income was earned evenly.

 

So, if your income is concentrated, for example, in the fourth quarter of the year you may be able to use the annualized income method. 

 

If this does not apply to you and your income is even throughout the year, you can divide your annual income by four for quarterly estimated payments. 

 

Click this link for more info on Estimated Tax Payments.

 

Yes, you can claim Itemized Deductions for your Mortgage, Property Tax, Charitable Contributions, Medical Expenses, etc. in the Deductions & Credits section. 

 

If you chose 'Explore on My Own' you will get a list of Deduction topics you can work on. 

 

This link gives details on Itemizing Deductions.