Are police lying when they say they wont charge you if you give them info to help their investigation?

Question:

Is it required by law to have to go to the police station and give DNA and fingerprints if you are only being accused of a crime and haven’t been arrested? Also, is restitution able to be a substitute for jail? Is there any alternatives a cop can offer instead of arresting you. Also, if you know police can acquire fingerprints should you tell them the truth before or should you go along with lying and hope that the prints are smeared/not able to be matched? Last question. Does confessing to a crime result in immediate arrest or is there a way to get at least a few days? & is there any ways to delay an arrest for example; can police give you a citation to appear in court for a crime you admitted too before deciding punishment? Or is there any reason someone was needed at home to take care of someone and got an alternative penalty.

Answer:

Right now you are a suspect in a crime, so you unless you want to incriminate yourself, speak to a lawyer first for advice. Anything you say can and will be used against you in a court of law unless you invoke your constitutional right to remain silent.