Creat Task or Sub-Project with dedicated cost and Income

Mates,
How to connect Sales Orders, Invoice, Purchase Invoice and other cost and incomes to the specific Task in the project?
Description :
I have a continues Purchase Order from client with same subject and my company wants me to bring all of them under one Project but separate in the diferent Tasks in such a way that all costs and incomes connected to that specific Task.

Hi @Poorya_bolooryan

You can make Task doctype as Accounting Dimension against which Budget can be defined and it will start controlling all of your income and expenses.

The whole accounting reporting mechanism will offer Task as a filter then to have dedicated reports for a single Task subsequently.

Thanks Ahsan,
May you please give me more details or steps to create the Task Doctype?