This page of the guide to Syberia: The World Before contains a beginner's guide, that all players unfamiliar with point-and-click games should read.
You'll use the mouse for all interactions with the environment and characters. Try to hover the cursor over different objects and every nook and cranny you see on the screen. Occasionally, when you're moving the camera, you may see elements that will indicate that you can interact with an object. As you explore a new corner of the city, try to find all available interactions to get even more familiar with the game world.
It's also worth taking the character to the end of the street, as the camera may turn around and reveal more explorable areas.
Listen to the dialogues carefully
The main protagonist's and other characters' lines are always important. By talking to important characters you learn what to do when the conversation ends.
People you meet on the street can sometimes help you find the place or person you are looking for. These people can sometimes tell you something interesting about the area or events related to the game's storyline.
You don't have to rush
There's no reason to hurry. You can search every corner of the area you're currently exploring at your own pace and look for new information about the plot or objects necessary to complete side objectives.
You have unlimited time to solve puzzles and riddles, and the intriguing story and non-linear chronology makes the gameplay very enjoyable and gripping.