I cant test this, but should it be something like:

# Example button configuration
button:
  - platform: template
    name: Livingroom Lazy Mood 1
    id: my_button

    # Optional variables:
    icon: "mdi:emoticon-outline"
    on_press:
      - logger.log: "Button 1 pressed"
  - platform: template
    name: Livingroom Lazy Mood 2
    id: my_button2

    # Optional variables:
    icon: "mdi:emoticon-outline"
    on_press:
      - logger.log: "Button 2 pressed"

As for the other thing, that might be something you need to write your own driver for? if you need some inspiration, this repo has a driver for mitsubishi heatpumps, which does something similar (read/write to a uart): https://github.com/echavet/MitsubishiCN105ESPHome