Trump's healthcare plan aims to repeal Obamacare and replace it with a system that allows cross-state insurance sales, health savings accounts, and Medicaid block grants to states. Repealing Obamacare could cause 22 million to lose coverage. Trump now says he wants to keep some aspects like coverage for preexisting conditions. The plan is evolving to include high-risk pools and language against abortion funding. Implementation faces challenges around insuring those with preexisting conditions and limiting coverage losses.