What did the 14th amendment do?

It basically included black ex-slaves as citizens of the US with all rights thereof. It overruled previous prohibitions against recognizing some natural-born Americans as citizens. It also placed other restrictions on the states that had formed the Confederacy.

The Fourteenth Amendment (Amendment XIV) to the United States Constitution was adopted on July 9, 1868, as one of the Reconstruction Amendments. Its Citizenship Clause provides a broad definition of citizenship that overruled the Dred Scott v. Sandford ruling by the Supreme Court (1857) that held that blacks could not be citizens of the United States.

Its Due Process Clause prohibits state and local governments from depriving persons of life, liberty, or property without certain steps being taken to ensure fairness. This clause has been used to make most of the Bill of Rights applicable to the states, as well as to recognize substantive and procedural rights.

Its Equal Protection Clause requires each state to provide equal protection under the law to all people within its jurisdiction. This clause was the basis for Brown v. Board of Education(1954), the Supreme Court decision which precipitated the dismantling of racial segregation in the United States. In Reed v. Reed (1971), the Supreme Court for the first time ruled that laws arbitrarily requiring sex discrimination violated the Equal Protection Clause.

The amendment also includes a number of clauses dealing with the Confederacy and its officials.

The 14th Amendment in 1868 stated that all persons born or naturalized in the United States shall enjoy full rights. This was done to protect the rights of freed slaves and minorities after the Civil War, but it applies equally to all Americans. The amendment itself states

Section 1. All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.

Section 2. Representatives shall be apportioned among the several States according to their respective numbers, counting the whole number of persons in each State, excluding Indians not taxed. But when the right to vote at any election for the choice of electors for President and Vice President of the United States, Representatives in Congress, the Executive and Judicial officers of a State, or the members of the Legislature thereof, is denied to any of the male inhabitants of such State, being twenty-one years of age, and citizens of the United States, or in any way abridged, except for participation in rebellion, or other crime, the basis of representation therein shall be reduced in the proportion which the number of such male citizens shall bear to the whole number of male citizens twenty-one years of age in such State.

Section 3. No person shall be a Senator or Representative in Congress, or elector of President and Vice President, or hold any office, civil or military, under the United States, or under any State, who, having previously taken an oath, as a member of Congress, or as an officer of the United States, or as a member of any State legislature, or as an executive or judicial officer of any State, to support the Constitution of the United States, shall have engaged in insurrection or rebellion against the same, or given aid or comfort to the enemies thereof. But Congress may, by a vote of two-thirds of each House, remove such disability.

Section 4. The validity of the public debt of the United States, authorized by law, including debts incurred for payment of pensions and bounties for services in suppressing insurrection or rebellion, shall not be questioned. But neither the United States nor any State shall assume or pay any debt or obligation incurred in aid of insurrection or rebellion against the United States, or any claim for the loss or emancipation of any slave; but all such debts, obligations and claims shall be held illegal and void.

Section 5. The Congress shall have power to enforce, by appropriate legislation, the provisions of this article.

it gave citizenship to African Americans born in the united states.

Full rights for all citizens, regardless of color.
The 14th Amendment provides citizenship to anyone who is born in the United States. It also grants them due process and equal protection.
made all black people citizens