Homework sucks, eh?
Your questions refer to ideas which are not necessarily universally recognized by historians. I suspect that the questions refer specifically to the discussions you've had in your history class, and that your teacher is expecting you to puke up what has been crammed down your unwilling throat. The best advice i can give you is to go through your textbook, go through your notes, and try to come up with these answers yourself.
What's that you say? You don't bother to take notes in class . . . a waste of valuable time when you can be texting your friends? Ah well, i don't know then how anyone will help you. Hey now . . . that sort of language is completely unnecessary.
Oh, alright . . . i'll go get you a link.
This page at Thinkquest
(clickity-click!) will tell you about the "Civil War amendments," which are also known as the Reconstruction amendments. They were proposed by Congress and ratified by the several states in the years just after the Civil War. The page for which i have provided the link is intended for use by students.
The 13th amendment prohibits slavery or involuntary servitude (means slavery by other means). The 14th amendment has some provisions to sanction states which don't guarantee voting rights, and to prevent those who fought against the United States in the Civil War from taking public office without the permission of Congress, and to deny any liability for debts incurred by the Confederate States. But the most important provision of the 14th Amendment is the due process clause, which prohibits any legal action which will deprive a citizen of life, liberty or property without due process of law. The 15th amendment serves as a primitive voting rights act.
Your question (or rather, your homework assignment) about what freedoms are strengthened by the Civil War, and how sacrifices made by people then affect us today are definitely matters which you can only answer by reference to what you have been taught in class, and what is in your textbook. You could get a thousand people who are very well-informed about the American Civil War, and get a thousand different answers to those questions. In all seriousness, i hope you took notes. If you didn't take notes, you need to get next to someone who did, and you need to carefully read your textbook in the section about the Civil War. Those are the only means by which you will be able to answer those parts of your assignment to the satisfaction of your teacher.
This is the last thing i can do for you--the text of the three "Civil War amendments":
1. Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction.
2. Congress shall have power to enforce this article by appropriate legislation.
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.
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.
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.
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.
5. The Congress shall have power to enforce, by appropriate legislation, the provisions of this article.
1. The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of race, color, or previous condition of servitude.
2. The Congress shall have power to enforce this article by appropriate legislation.