Custom Avatar creation endpoint not found in API documentation

Hi,

I a developer and I recently signed up to the HeyGen community to start digging the publicly available API. My goal is to make an application using HeyGen API and integrate avatar video generation inside my application.

I want to integrate the following functionalities:

Custom avatar creation
Video generation: https://docs.heygen.com/docs/create-video#2-generate-video
Video generation status checking: https://docs.heygen.com/docs/create-video#3-check-video-generation-status
Video download: https://docs.heygen.com/docs/create-video#download-the-video

I have found almost all necessary endpoints. However, I don't find any information about the custom avatar creation endpoint. I only see that the custom avatar can be created using HeyGens dedicated page. My goal is that let users in my app create a custom avatar of themselves and then use it later by providing an input text.
They should be able to create a video using their personal avatar, talking the text they have provided. Afterwards they should be able to download that video.

Can you help me?

Thanks in advance. Regards,

Eneko