Here are some of the major provisions of the Republican bill. It is far more complex than the ACA, but I'll do the best I can. All of the examples are based on a single person, not families. Families would get a bit more, but still not enough.
1) Larger employers will no longer be required to offer coverage to their employees. This is done by eliminating penalties for those who do not provide this converged. Many employers will chose not to buy insurance for their employees and thus throw them on the more expensive individual market. Many will not be able to afford this insurance and will thus lose their insurance altogether.
Individuals will no longer be fined for not carrying insurance. Without fines, many who are healthy will no longer get insurance. This will increase premiums enormously since the pool of remaining subscribers will more likely become sick and file claims. (The risk to the insurance company will not be spread across a large pool of the healthy and the less healthy.)
2) The ACA rules that required all insurance plans to cover hospitalization, maternity care, and mental health care are eliminated. It will be up to each state to impose all, some, or none of these requirements.
3) The surcharge on high income taxpayers, which was included in the ACA to help pay for it, has been eliminated. It is estimated that this will reduce revenue by $600 billion over 10 years.
4) There will be subsidies in the form of tax credits to help people buy insurance. With ACA, these subsidies were paid directly to the insurance company. (I assume that the tax credits in the Republican bill will not be available until the end of the tax year when tax returns are filed.) I also assume the these subsidies will be available to the many millions who do not make enough to pay federal income tax. I further assume it will work the same way as the Earned Income Credit—even though a person's income is so low that they do not have to pay income tax, they can file for the credit and receive a "refund" anyway. (I would be greatly surprised if a majority of Republicans will support this "giveaway." Most likely, the very poor will end up not getting a subsidy at all.)
With ACA, the amount of subsidy was based income; with the Republican plan the subsidies are based on age. The subsidies are $2000 for younger people going up to $4000 (max.) for older people. Thus, older people get twice as much as younger, but insurance companies say that premiums will be 5 times higher for the elderly. (This is like sending down a 20 foot rope to help someone out of a 50 foot hole.) Every older person would get the $4000 even if they are wealthy and do not need it. (Republicans do believe in equality!)
The $2000 subsidy for younger, low-income people would not be nearly enough for them to get good insurance. (ACA subsidies were much higher for the poor; they increased as income decreased.) Most people will only be able to afford catastrophic insurance under the Republican plan.
5) States that accepted the 90% federal reimbursement and put all people below a certain income level on Medicaid, will continue to receive that subsidy until 2020. (The next presidential election is in 2020.) But after that, these states will have to pay for Medicaid themselves. The 19 states that opted out of the ACA Medicaid program will receive grants totaling $10 billion for five years. This will be used mostly to reimburse hospitals for caring for the poor. These will be people who use the most expensive health care—an emergency room. Gone are the provisions of the ACA to encourage preventative medical care. (Before ACA, often those who could not afford to be seen by doctors on a regular basis, would finally show up in an emergency room when care requires acute and expensive treatment. For some, it is too late.)
The good news is the provision that children up to 26 can remain on their parents' insurance plan remains. Also, insurance companies must insure those with pre-existing conditions. But if, for any reason (such as losing a job), someone is without insurance for more than 2 months, when they try to get back in they will be charged a premium 30 percent higher than those with continual coverage.
In short, the wealthy will get most of the benefits of the Republican plan and the neediest will be on their own. The Republicans tout this as allowing freedom of choice. The choice is between getting insurance that you cannot afford or suffering from some disease or possibly dying.