How to notify using TTS — and much more

Hi,
I’m trying to transform this rest_command to a notify :

rest_command:
tts:
url: ‘http://11.6.168.112:12101/api/text-to-speech?SiteId={{ site }}’
method: ‘POST’
headers:
content_type: ‘text/plain’
payload: ‘{{ lemessage }}’

The notify i’m trying to debug … but i’m stuck.
Could you help me ?

notify:

how can we set volume level for tts in configuration.yaml ?

how can we set volume level for tts in configuration.yaml ?