Security First Act This bill provides statutory authorization for the Operation Stonegarden program from FY2022 through FY2025 and contains other provisions related to border security. (Operation Stonegarden provides grants to enhance the border security capabilities of state, local, and tribal governments.) From FY2022 through FY2025, the money from unreported monetary instruments seized from individuals crossing the U.S.-Mexico border and transferred into the Department of the Treasury general fund shall be made available without further appropriation to the Department of Homeland Security (DHS) to fund Operation Stonegarden. DHS shall report to Congress on (1) DHS hiring practices from 2017 to 2020, and (2) whether certain Mexican drug cartels meet the criteria to be designated as foreign terrorist organizations. DHS shall also periodically report to Congress about the technology needed to secure the U.S.-Mexico land border.