You don't have to enter meal expenses.  M&IE are based on your layovers, which has the benefit of allowing you to write off meals without receipts and results and a bigger M&IE deduction.  This is referred to as the per diem deduction because city-by-city per diem rates from the GSA and and Department of State are used to come up with the amounts you are allowed to deduct.

That might seem a bit confusing, but think of it this way.  If you travel on a trip with an overnight, you are eligible to write off M&IE expenses.  Rather than keeping actual meal receipts, you can use the per diem rates for the cities you were staying at.  EZPerDiem connects the airport codes of you layovers to those per diem rates, so you do not have to look them up.  You just enter you layovers in the Layover Entry Page next to the dates they occurred.  The date is important because the per diem rates are dependent on the location and the date.

The other expenses that you write off for work go in the Expense Processor.  You can see what most of those are with this article:

Airline Expenses Listed and Explained

IMPORTANT:  YOU ONLY BENEFIT FROM THESE DEDUCTIONS IF YOU ITEMIZE

Generally, if you do not have a mortgage on a house, the M&IE expenses and other aviation employee expenses will not reduce your tax liability because they are considered an itemized deduction.