Social Security for Future Generations Act of 2019 This bill increases specified benefits and taxes related to the Old-Age, Survivors, and Disability Insurance (OASDI) program and otherwise modifies the program. Changes to benefits include increasing the primary insurance amount for certain beneficiaries; revising the method for calculating cost-of-living adjustments by using a price index that tracks the spending patterns of older consumers; extending benefits through age 22 to full-time students who are eligible children of deceased, disabled, or retired workers; establishing a new minimum benefit for certain lifetime low-earners; and establishing an alternative benefit based on combined household benefits for widows or widowers in two-income households. Changes to taxes include subjecting earnings in excess of $250,000 to Social Security taxes. No taxes shall be applied to earnings between the contribution base (the maximum amount subject to the Social Security payroll tax, set at $137,700 for 2020) and $250,000. In addition, the bill preserves eligibility for Supplemental Security Income payments and other means-tested programs by limiting the amount of OASDI payments considered in eligibility determinations.