Form 8379 is for an Injured Spouse Allocation - https://www.irs.gov/forms-pubs/about-form-8379
Complete, print, sign, date and mail the form to the IRS.
See this TurboTax support FAQ for a Form 8379 - https://ttlc.intuit.com/community/accessing/help/how-do-i-file-form-8379-injured-spouse-allocation/0...
