Whether a young person may be found guilty of a crime depends upon whether the crime in question is one which requires a heightened level of intent. If a person is really, really young, like two years old, they lack the mental capacity to commit a crime of specific intent. In most jurisdictions it is a fact of law that under the age of 12 is not capable of the mens rea required to commit a crime.
More practically speaking, the better question would be "How old does one have to be in order to be prosecuted as an adult?" If that is the question you intended to ask, then the answer depends upon the source of the criminal law allegedly violated. In other words, the answer differs from state to state.
blame
The reason for Nero's persecution of Christians may be attributed to the Great Fire of Rome in 64 AD. The city was reduced to rubble and although many thought that Nero may have been responsible for the blaze, a few sources say that Christians may have confessed to the crime, although by free will or by torture is unknown. Because of this, Nero and the community placed the blame on the Christians, and thus they suffered greatly, by being crucified, thrown to dogs, and burned.
No, not unless there is new evidence. To retry a person for a crime who has all ready been found guilty or innocent is double jeopardy and not allowed under the constitution.
If a person is found guilty of a crime, the judge or jury determines their sentence. This may include prison, it may include execution, it may include probation or any number of alternate sentences.
You can be factually guilty without being legally guilty. You may have actually committed the crime, but if it can't be proven in a court of law you aren't legally guilty.
Acts where they have been found guilty of transgressing the laws of the country involved. Countries have different laws and what may constitute a crime in one place may be legal elsewhere.
They have been found guilty of the crime. The court will then set the sentence for the offender. It can be jail or prison time or may be a fine or restitution or even a combination of these.
... may or may not be convicted of the crime ... At least in the USA... On the other hand if there is reasonable doubt that a person is guilty of a crime, he or she is supposed to be acquitted (which is not the same as declared innocent).
There is no sentence for a search warrant. If, during the search, evidence of a crime is found, a criminal charge may be filed. The sentence, if a person is found guilty of the criminal charge, will depend upon what the criminal charge is.
In law guilty means having been deemed responsible for the commission of some crime. That may be as the result of a decision by a jury, judge or plea bargain.
Being charged with the crime is a formal accusation by the Crown Prosecution Service (CPS- In England and Wales) that you have committed a crime. In the USA, the law enforcement or prosecutor charges I am led to believe. Same principle however. *It certainly does not mean you are guilty, and everyone is innocent until proven guilty by a court of law. It then has to go to court for a conviction or acquittal (guilty or not guilty) Thus, a conviction is basically a finding of guilt for the charge by the court (who represent the state and the community at large) that you have committed a crime and are to be punished for such offence, this is sentencing.
A jury or court finds that the accused is not guilty, in reality the accused may not innocent.