“They scrap federal tax and leave fica”
FICA is the payroll tax. It’s the tax that Trump is talking about scrapping. FICA - the payroll tax - funds Social Security
See:
https://www.investopedia.com/terms/f/fica.asp
Why Trump would talk about eliminating the funding source for Social Security just before an election, is beyond me
As I understand it, fica is only SS and Medicare, and Trump’s EO only defers the employee paid portion. Employers would still be liable for their part. The federal income tax as well as state and local taxes would still be in place.