The first step a person should take before filing a criminal case is reporting the incident to the police.

Here's how it typically works:
Report the Crime to Law Enforcement:

Visit or call the local police station.

Provide a detailed account of the incident, including names, dates, locations, and any evidence or witnesses.

The police will then create an official First Information Report (FIR) or incident report, depending on the jurisdiction.

Police Investigation:

After the report is filed, the police may begin an investigation.

If sufficient evidence is found, the police may arrest the suspect and forward the case to the prosecution.

Filing Charges:

The prosecutor (district attorney or equivalent) will decide whether to file formal criminal charges in court based on the police investigation.

The first step a person should take before filing a criminal case is to identify the nature of the offense (cognizable or non-cognizable) and collect all relevant evidence and details about the incident. This includes making a detailed note of what happened, when and where it occurred, and who was involved, as well as gathering supporting materials like documents, photographs, or witness statements.
If the offense is cognizable (serious crimes such as theft, assault, or murder), the next step is to approach the nearest police station to file a First Information Report (FIR), either orally or in writing. The FIR serves as the official starting point for police investigation. For non-cognizable offenses, or if the police refuse to register an FIR, the person can approach the court directly with a private complaint.
Consulting a lawyer before filing the complaint is also advisable to ensure the correct procedure is followed and all necessary legal details are included.