Hello Mohamed,
There is no one answer to this question as it depends on many factors related to the organization among which is the organization's structure, size, industry, culture, standards,etc. In some cases the PM may report to Project management office (PMO), delivery or account managers, senior manager, Director, etc.
Training for Project Management Professional (PMP)®, PMI Agile Certified Practitioner (PMI-ACP)®, and Certified Associate in Project Management (CAPM)®