It sounds like you have been charged in a 10-count federal indictment. This means that a federal grand jury has found that there was probable cause you committed 10 federal crimes. Each charged crime is a count. They can be different, or some may be the same thing on different occasions or with different alleged victims. You mention it is a conspiracy charge, which mean that the government believes you entered into an agreement with one or more other individuals to commit a crime and that you did some act to further that endeavor. Extortion appears to be one of the crimes they believe you conspired to commit.
It is extremely difficult to determine your potential sentence in a federal crime with the facts given, as the computations are very different than if it were a California state crime. Your criminal history, the exact charges you are facing, and the amount of extortion or attempted extortion all help to determine the sentence.
Wiretaps are legal anywhere in the United States, as long as they follow certain guidelines and the government obtains a warrant. Federal and California State wiretap warrants have different guidelines. Since your case is federal, it likely arose out of a federal wiretap. In order for the government to wiretap your phone, they must obtain a warrant to do so from a judge. Typically, the government must show probable cause that you are involved in a crime, and that normal police efforts have been or will be ineffective for a federal magistrate to grant a warrant for a wiretap. Ten to fifteen years ago, wiretap warrants were few and far between. However, in the last ten years, judges have been eager to grant warrants for law enforcement to do so.
It appears that you are involved in a serious federal criminal conspiracy, and I highly recommend that you hire an experienced federal lawyer to represent you right away.
Best of luck.
It means that there are 10 counts in the Indictment. Whether you are charged in all ten counts is not clear (I do not know if there are co-defendants). Wiretaps are legal - law enforcement/the prosecutors apply for them and a judge can permit them.
The sentence you are looking at will depend on many factors: the seriousness of the charges against you, your role in the charges, your prior record, etc. You should consult an experienced federal criminal defense attorney immediately.
It means there are 10 charges. In federal cases, there may well be some counts for some defendants and not for others. Sentencing would depend on a number of factors too difficult to explain here. The most important thing for you is to quickly get a good criminal defense lawyer to represent you on the case; this is too important to try and deal with on your own.