how to use POST API call#?

Hello, I am creating a FAQ custom chatbot and I want the chatbot to be able to collect some info from clients and send it to a third party email address using the POST API call in Voiceflow. I created 3 entities namely; client_name, client_email and client_phone which contains some info on the client and I want to send these info to a third party email but don’t know how to go about it. For example, name:ck , email: zuzu@gmail.com , phone: 7743108745 ..I want to be able to send info like this to a third party email address but I don’t know how to go about it. Pls help