ERPNext customisation for solar company EPC

Newbie to erpnext after installation with default modules on server what should i do to custom solar management company. i need project has tasks , tasks has purchase order, workorder and payment expenses for each project. how to implement with custom fields and how to hide or delete herited fields . kindly someone guide me to start idea or is there any good tutorial for me . advance thanks to someone.

https://docs.erpnext.com/docs/user/manual/en/project

Hi @pravin_doss ,
Is this Solar Company comes under Kerala State ? If yes , can you please contact me on sebinpsabu900@gmail.com ?
My previous company have an ERPNext application which is used by many solar companies.
If interested, please do contact me on the above mail.

it is in tamilnadu also i have implemented erp in odoo, laravel php js and bootstrap also new to erpnext .
Try to learn for upcoming projects.