My husband did not give me his w-g2 forms for 2016 how do i fix this problem?

If you need to enter additional information, delete something, or change something on the the tax return you already filed, you have to wait until your return has been fully processed, then you can prepare an amended return, called a 1040X.  You cannot e-file a 1040X.  It must be printed, signed and mailed to the IRS.

https://ttlc.intuit.com/questions/3061514-how-do-i-amend-a-2016-return-in-turbotax 

After you print, sign and mail your amended return—1040X— to the IRS wait about 3 weeks and then you can begin checking on it at the IRS website.  Be aware that it can take at least 3-4 months for an amended return to be fully processed (or sometimes even longer.)

https://www.irs.gov/Filing/Individuals/Amended-Returns-(Form-1040-X)/Wheres-My-Amended-Return-1

Gambling

To enter the W-2G  or other documents For your Gambling winnings--Go to Federal>Wages & Income>Less Common Income>Gambling Winnings

You can enter your winnings, and then keep clicking through the interview to enter gambling losses.

Gambling losses are an itemized deduction; you can only get a deduction if the combination of all of your other itemized deductions exceeds your standard deduction.  Losses do not offset winnings dollar for dollar.

https://www.irs.gov/help/ita/how-do-i-claim-my-gambling-winnings-and-or-losses