Do keep in mind that the social safety net does vary from state to state, though compared to the UK it’s pretty threadbare everywhere.
In my state, you’d qualify for food stamps when your assets dropped to $2,000 or less, you could get onto the Section 8 subsidized housing waiting list which is 10 years long to get subsidized housing. Since, presumably you would lose your home prior to reaching the top of that list you’d be referred to local homeless shelters. You would not qualify for Medicaid until you were officially decreed permanently and completely disabled - which might never happen if you can walk at all, use your hands, and talk no matter how messed up you are otherwise. No, let me rephrase that - you can be missing body parts and/or in a wheelchair and still be told you don’t meet the requirements for disabled because in theory you can do job A, B, or C, nevermind there might not be any such position in a hundred miles or it requires training you don’t have. The process of being decreed disabled generally takes 2-3 years, and often multiple appeals before final determination. At that point, you’d get a monthly stipend, your food stamps would then be slashed to $50 a month, you’d get on Medicare, where you have to come up with 20% of all medical costs, which comes out of your stipend, and maybe Medicaid would pick up some of that 20%. As the stipend isn’t nearly sufficient for monthly rent in many areas of the country you’d probably either half to find a roommate, be homeless, or wind up in a nursing home, a condition of which is signing over all your income to them except a token amount so you can purchase things like “toiletries” and hope to god no one steals what few possession you have left from your room.
Until you qualify for Medicaid (state level medical assistance) or Medicare (Federal level), if you are in immediate danger of death you can get treated at an ER to the point you are no longer actively dying, at which point you will be put back on the street. If you aren’t actually dying - just in a lot of pain, for example, or just gradually losing a body function - you’re out of luck unless you can find a free clinic or manage to beg some charity.