Pre-populating a field from another DocType

[NCP]

Please check the videos.

How open new doc with all data in object

I have given the reference of the video here, maybe it will help someone. [Populate Data From One DocType To Another Using frappe.new_doc | Frappe | ERPNext]

Fetch Child table form one doctype to other doctype

I have given the reference of the video here, maybe it will help someone. [Fetch Data From One DocType To Another | Frappe | ERPNext]