After you have placed the keys at the base of the Sphinx, you will reveal the passage ahead. The Cross the gate and, at the end of the path, use the figurine to open the way up ahead. Climb onto the fragment of the stone stairs, climb up, grab onto the stone ledge and jump onto the vines on the wall. Continue up the stairs until you reach the very top.
Here, you will have to solve a quite unique puzzle. You can shove the stone, as a result of which the time of the day changes. The point of the puzzle is to manipulate shadows - position the orb just like in the above screenshot. Then, jump onto the stone block on the right. The shadow will correspond to the shape on the wall, and you will unlock the passage ahead.
Go towards the mysterious person in the cape and the fox. Use the figurine, which will open the passage ahead. Follow along the glowing ground and in front of the wall with the key painted on it use your character's voice. Follow the corridors and go through the narrow passage. Go through the locations and reach the spot where there is wind blowing - use your character's scream to remove the pitcher and walk inside.
Run down the corridor and follow up ahead until you reach a large and dark chamber. Go right and try to walk around the interior of the chamber - keep approaching the glowing figurines up until you reach the centre of the chamber, where the figure in the red cape was. Go through the passage and jump down to the very bottom.
Keep going up ahead until you reach the chamber with a huge staircase. Keep going up - there is quite a long way ahead. Finally you will reach a huge shining passage - keep going ahead and enter the light to travel to a completely different location. This is the end of the first chapter of the game.