Hi
I have quite a lot of experience in setting up and running PMO (as a part of performance improvement and turn around projects)
In short what you need:
1. Agreed with your boss framework in which projects will reported to you and steering committee or other supervision body. You need also some tool to help you with seeing where you are and making reports. I used Excel (with VB macros) and Google Sheet. For more advance solution you can use Asana, SmartSheet, Lean Kit,
2. Agree on how projects should be run – how often you meet with PM, how often PMs are meeting with their team, how team leaders are chosen, how resources are allocating to the project and who decides on this; what is the reward / motivation scheme for PMs and team members
3. Communicate it to the project leaders / stream leaders – I proposal to make a training and presentation available to everybody – record it so that you do not have to answer stupit questions time and again
4. Execute and improve
That is in short
If you want to have a look at the excel just write to me

Best regards
Asen

I have started several PMO departments for companies that have demonstrated a need to have one.

The objective of a PMO department is to centralize how you are delivering projects. It usually happens when you have too many projects, or ill equipped project managers and there is misalignment between your projects and your company's objectives.

The nature of a project is to create a change within the organization. When you have too many projects, you have too many competing changes in progress.

There is not a single strategy on building a PMO department because the business rationale for one will vary. For this reason, starting a PMO department should be treated as its own project. Define a business plan, change management plan, budget, and ensure you have stakeholder support. Only until you have done the proper research and planning should you embark on building a PMO department.

PMO departments will carry serious overhead and your organization needs to weigh the pros/cons of this based on the changes your organization is trying to undertake using a project management approach.

The first step in establishing a PMO is to analyse the current situation. Look at the PM methods, processes, and tools used so far. Scrutinize the most important current projects for weaknesses. A project worthiness analysis tailored to your company will help you make this decision. Without a complete list, you will have no idea what people in the company are really working on. This list provides the up-to-date and accurate information needed for the portfolio reports management uses to make decisions. Remember to take a close look at your company’s existing project management processes. One important factor is your company’s organizational structure. Take a close look at the training opportunities and career paths available to those involved in project management. Your findings will help you determine the level of project management expertise in the company. Not everyone in the company will be enthusiastic about the creation of a PMO, so you will need all the good feedback about positive changes that you can get. The PMO is a service provider whose success depends on the satisfaction of its “customers”, namely, the stakeholders in the project environment. Each of these stakeholders has their own expectations of the PMO. Once you have established a PMO, it is a good idea to start by focusing on only one or two of these responsibilities. Stakeholders often tend to overburden the PMO with activities. It has one key responsibility ‒ the one derived from the stakeholder analysis ‒ and this should always be its primary focus. Get stakeholder input and agreement on this.
Besides if you do have any questions give me a call: https://clarity.fm/joy-brotonath

Here are some key objectives to consider when building a PMO department:
1)The primary objective of a PMO is to enhance project success rates by establishing standardized project management practices, providing guidance and support to project teams.
2)A PMO can help to optimize resource allocation ensuring that the organization's resources are effectively utilized.
3)A PMO plays a crucial role in establishing strong project governance structures and providing accurate and timely project reporting to stakeholders.
Remember, the objectives and strategies of a PMO can vary based on the organization's size and industry.