Medicaid has different income limits for different states. For a family of 3 in Michigan it's about 2755 per month. If you make less (per household) you qualify for Medicaid. Search "Medicaid Requirements" plus your state. Everything is covered. The 2400ish we bring home a month barely covers our bills, but it's worth it for Medicaid if you have a chronic health condition (or on our case my spouse, our child, and myself all have serious health conditions). My medication for my pituitary deficiency would cost me thousands a month. My spouse and child have a genetic vascular condition and they need scans every year to make sure they're not about to die.
Another thing you can do is a Medicaid spend down. I'm not sure how it is for every other state. But let's say your limit is 3000 for your family but your income is 4000 and your medical bills are 2000 a month. You pay the difference between your income and the limit (1000), and Medicaid covers the rest. I believe you have to have a serious health issue to qualify for a Medicaid spend down.
If you are low enough income to qualify for SSI, Medicaid is given automatically (I think in every state).
In our state of Michigan you apply for Medicaid at DHHS. They have a very easy to use website for a few years now (it was a big hassle before that). Let me know if you have more questions about this.