Help rewrite fan config

Can someone please help rewrite this piece of config so that is works again with home assistant.

  - platform: mqtt
      identifiers: nrg-itho-1
      model: ITHO Wifi Add-on
      name: ITHO-WIFI
    availability_topic: itho/lwt
    unique_id: nrg-itho-1
    name: nrg-itho-1_fan
    state_topic: itho/lwt
    state_value_template: '{% if value == ''online'' %}ON{% else %}OFF{% endif %}'
    json_attributes_topic: itho/ithostatus
    command_topic: itho/cmd/not_used/but_needed_for_HA
    percentage_command_topic: itho/cmd
    percentage_command_template: '{{ value * 2.54 }}'
    percentage_state_topic: itho/state
    percentage_value_template: '{{ ((value | int) / 2.54) | round}}'


Start by explaining what doesn’t work. Also provide information about the topics and the values in the topics.