Hello.
I want to create post via API and I need to set featured image and post date for example 2020.02.02
Your best bet for this is the Admin API Documentation:
First of all i read this document but I didn’t find info about featured image and post date
All the fields are listed in the post object section - i.e. feature_image
, feature_image_alt
, feature_image_caption
, and published_at