Walking in the forest only returns you back to where you started. You would need help from a local.

Advance other stuff until someone willing to help appears. ?

The crying boy at the forest entrance is the local guide for you. Talk to him.

You have to be nice to him.

Answer these options:

You have to talk to the mushrooms. You should do that in the second forest scene.

Yes. There are two mushrooms in every scene. They will tell you about the destination you should pick. The catch is that the other will always tell the truth while the other lies.

You would need to deduct which one is lying and which one is truthful.

Of the presented questions only two questions really matter. ?

Let's see, we have two mushrooms, Left and Right. They could, for example, answer like this:

Now, test the answers so that either Left or Right is lying. Only the one option will work as the mushroom should lie also in the "Which path would the other..." question.

The correct option in this example is ?

Yes. Ask first "Which path leads...", you get two directions. Then ask "Which path would the other..." you get only one direction from both mushrooms. That single direction is the incorrect one. You should go to the direction they didn't say as answer to the "Which path would the other..." but that was answered in the first question by either of them.

For example:

The correct direction in this example is east. These will differ from game to game so you must just ask the questions and walk into the correct direction. If you end up in the beginning screen, you made a mistake.