PSM or PSPO which one I should begin with

I would recommend starting with the PSM I certification, regardless of your role on an agile team.  This is Scrum.org's most popular certification and the one the most people will be familiar with.  It covers the basic frameworks discussed in the Scrum Guide and ensures that you are ready to work on a Scrum project and follow Scrum best practices as they're written.

From there you have a few options, which I'll list in order of my personal perception of difficulty.  The SPS can be taken at any point (preferably after the PSM I) to support all roles in larger enterprise environments.  Product Owners would be supported by the PSPO I, which covers backlog management and communication.  Developers would benefit from the PSD certification, covering test-driven development and integration of work between multiple teams.   Scrum Masters will find the PSM II valuable, by digging into more complex topics that go beyond Scrum as it's written, and into Scrum as it's applied.

Finally, you can look at the top-tier certifications once you've selected a role to focus on.  The PSM III and PSPO II both contain intensive essay questions which will require experience and critical thinking for how best to handle dynamic situations.  There is likely to be a PSD II added sometime in the future.  These all seem like very challenging exams, and I wouldn't approach them without real-world experience.

So since you appear to be interested in a Product Owner track, my recommendation would be:

1. PSM I
2. PSPO I
3. SPS
4. PSPO II

A Scrum Master's responsibilities include being an agile coach. He or she ought to be able to help PO's, developers, and organizational stakeholders to understand Scrum. On that basis it may be advantageous to start with PSM, and thereby cultivate a broad understanding of the entire framework and its roles.

Thanks You Jason. Very Clear and details information.