Okay I need some help on how the whole courtoom system works for different cases. How does the court handle child custody cases and Murder cases? Like i know courtroom terms like "objection" but how dont know how that term is used in courtroom. When is the right time to use it. As well as "Testify"... Like what does that mean in courtoom? Like what other terms are used during courtroom cases and how are they used? and how are cases between child custody and murder cases are handled?
This is not likely to be something that you can get answered in a forum post. It's probably going to be weeks of researching, or more. Perhaps people could suggest appropriate books for that research.
These are vary vague questions, and it would probably help to hear your problems in the story to figure out how we can help, or have you not come up with much of it yet? Do you read other books or watch movies set in courtrooms where those words are used, so you know what they mean? As for murder and child custody, well it depends on the case and situation.
"Objection" would be used by one of the barristers if the opposition barrister was breaching the rules of courtroom procedure as to what is allowed. An example might be if he was "leading" his witness, e.g. he's allowed to say "What did you see on the night of the fifteenth?" He's NOT allowed to say "Did you see the defendant standing over the victim, with a knife in his hand, on the night of the fifteenth?" Another example might be if the line of questioning doesn't seem to be relevant to the case, e.g. questioning the witness about the defendant's marital infidelities when he's accused of robbing a bank. However, I'm not a lawyer, just somebody who's picked stuff up over the years. John Grisham, on the other hand, earned a living in the law before he started writing novels about it. I'd suggest that if you're looking for advice on basic terms, you need to do a LOT more - and more detailed - research.
If it's possible, see if you can get to spectate some courtroom hearings (if that is possible where you live). Asking people and researching in a library is one thing, but getting first-hand experience would definitely be gold. You might not be able to catch a murder case, but it should still help a lot with atmosphere and the general procedure.
In the U.S. this stuff can vary between state and federal court. Look at the Federal Rules of Civil Procedure online and how this all works in federal court will be layed out. You can also get the Federal Rules of Evidence online, which will have lots of other useful information if you're going to have a courtroom scene.
Research, dude. Do it yourself. Ask questions on this forum about plot and character design. Realistic context might come into it, but if it's just research, go elsewhere.
For clarity, you should specify the jurisdiction you're using. (Since you didn't specify, I suspect US - Americans seem to be the ones most likely to assume their system is universal! But it would be good to clarify, anyway). And you should look for more specific questions - this is way too general to really answer.