The QBI Deduction is calculated by netting the total amount of qualified income, gain, deduction and loss from any qualified trade or business. This includes only items that are taxable income and are connected with a trade or business in the United States. Capital gains and losses, certain dividends and interest income are some of the excluded items.
The program will automatically calculate your QBID based off of your business income entries.
For more information, please review these related articles.
What is Qualified Business Income (QBI)?
What is the maximum I can earn and still claim the 20% small business deduction?