Expands access to federally funded health coverage by treating people who are lawfully present in the United States as eligible for Medicaid, CHIP, premium tax credits, cost‑sharing reductions, and Exchange enrollment; requires states to provide Medicaid/CHIP to lawfully present noncitizens who meet other eligibility rules. Allows states to opt in to provide full Medicaid/CHIP to people without lawful immigration status, removes or changes several immigration‑based barriers in the Internal Revenue Code and the ACA, and directs federal agencies to create an enrollment pathway (including a special enrollment period) and adjust program rules. Many tax/ACA changes take effect for plan/tax years beginning after December 31, 2025, while some enrollment actions must begin within 90 days of enactment for people with federally authorized presence.