Project must show the information taken from timesheet-based custom doctype

I created a custom form starting from a copy of the doctype timesheet and I need the data saved inside it (at least the most important ones such as the number of hours or the customer) are also displayed within the corresponding project, exactly as it happens for timesheets.
I want to remind you that for a project there can be multiple instances of this doctype and some mathematical operations (such as the sum of the hours) must be performed.
I have no experience with the frappe framework and I can’t find any valid documentation to achieve my goal.
can someone explain me a method to do it or provide me with links to understand how to solve the problem?
Thank You