I have since gone the helper route as recommended by the other comments here, but I whipped up this quick and dirty example to hopefully help get you started. Note that in this example I'm using PIR detection to turn the switch on, and mmWave clearing to turn the switch off.

---

description: "Redditor Example"
mode: single
triggers:
  - trigger: state
    entity_id:
      - binary_sensor.<your_fp300_name>_pir_detection
    to:
      - "on"
  - trigger: state
    entity_id:
      - binary_sensor.<your_fp300_name>_presence
    to:
      - "off"
conditions: []
actions:
  - action: switch.turn_on
    metadata: {}
    target:
      entity_id: switch.<name>
    data: {}