Take the paper from under the chair.
Take the key from the corner. Open the desk and take stamp and the stamp pad. Click on stamp and then stamp pad to put ink on stamp.
Go and stamp the paper on the table with signature on it to get the date June 28 2016. Also note the red and blue color on paper, plus the yellow on your paper.
Look at the calculator (note the 9 is different from the rest of the numbers).
Go to the screen.
Zoom-into the screen next to the door:
Puzzle 1: See the text (Summer, Winter, Autumn, Spring) and a color box (Green, Red, Blue, Yellow). Answer is Summer (see the post date) and Green (The only color amongst the options that does not have a + in that color).
Puzzle 2: See two stars. The answer is 45 (5*9)
Proceed to the next level!