A routine stop feels a lot less intimidating once you know exactly what you're required to hand over and what isn't actually being asked of you.
As a general matter, you can expect to be asked for your driving license, the vehicle's registration, and its fitness certificate — carrying all three (or valid digital copies, where accepted) resolves most stops in under a minute.
If a dispute arises over an alleged violation, note the officer's name/ID and the specific provision cited if possible — this is what makes any later appeal or clarification possible. Escalating on the spot rarely helps and can complicate things.
This is general orientation, not advice on a specific incident. If you've already received a citation you believe was wrongly issued, that's a different, more specific question worth asking directly.