This summary is not the rule. The rule text controls.
If a person has been charged with a crime and must answer to it in court, either side, the defendant or the state, can arrange to have a witness questioned ahead of time. This is called a conditional examination. It can happen before or after formal charges are filed.
This process exists mainly to protect testimony that might not be available later. For example, if a witness is very sick, elderly, or planning to leave the area, their statements can be recorded and preserved under oath before the trial actually starts. That way, if the witness cannot appear in court when the trial happens, their earlier answers can still be used as evidence.
The rule also makes clear that this is the only proper way to question a witness ahead of trial in this situation. Both the defense and the prosecution have to follow the specific steps laid out in this part of the law. They cannot use some other informal method to get a witness's testimony early.