Now I have to write some code. After some thought, it would be best if I had the following control
options:
- set level 1
- set level 2
- set level 3
- ventilate for 30 minutes

I noticed that 100ms is not enough to press the button. With a value of 500 ms, pressing the keys works stable.

The following is the ventilation level 2 code as an example:

// STAGE 2
On stage2 do

  // 4 X CLICK DOWN
  Pulse,14,1,500
  gpio,14,0
  Pulse,14,1,500
  gpio,14,0
  Pulse,14,1,500
  gpio,14,0
  Pulse,14,1,500
  gpio,14,0
  Pulse,14,1,500
  gpio,14,0

  // 2 X CLICK UP
  Pulse,12,1,500
  gpio,12,0
  Pulse,12,1,500
  gpio,12,0

  //RESETGPIO
  gpio,12,0
  gpio,13,0
  gpio,14,0

endon

Now I can integrate the whole thing into my smart home and control it as I like. Unfortunately, I
haven't received the VOC sensor from Aliexpress yet, so I have to wait with the VOC-controlled
ventilation.