The ERA is a proposed amendment to the Constitution that would end legal distinctions between men and women on a variety of matters. Supporters of the ERA note that the Constitution lacks a specific guarantee for equal rights protections on the basis of sex. Opposition to the amendment comes from two fronts: some posit that women do need special protections especially in areas of labor law while others base their opposition on a defense of traditional gender roles.
House Joint Resolution No. 638 extended the deadline for ratification to Jan. 30, 1982, but Congress may not have the authority to do so. There was vigorous discussion in the popular press and among legal scholars, but the conversation stalled as even with the extension there were not enough votes to ratify. The question was revived in 2018 when Illinois voted to ratify, but the question has never been fully settled.
For an introduction to this issue, see this short piece from the American Bar Association. This article from the Indiana Law Journal lays out the arguments and sources of ambiguity around the question of reversing ratification. For another discussion of the issue, check out this article from the Louisiana Law Review.
The ability, or lack thereof, to access the full range of choice about family planning options doesn't just affect cisgender women, but it does usually get grouped under "women's issues." It's important to remember that not every person with a uterus is a woman, despite the cisnormative language prevalent in these discussions.
In the United States, the access to abortion procedures is currently protected by the Supreme Court's decision in Roe v. Wade.
The Hyde Amendment restricts abortion coverage for patients receiving federally funded healthcare assistance except in cases of rape, incest, or where the life of the pregnant person is in danger. It does not restrict those people from paying out of pocket, but it does prevent the use of federal funds to pay for abortions. This is one of many types of legal restrictions on abortion access.
Access to abortion varies by country. Focusing on North America, in Mexico the legality of abortion is a states rights issue and access varies and in Canada it is legal at all stages of pregnancy, a right governed by the Canada Health Act. A good starting place for more international research is the Wikipedia Category "Abortion by Country."