Oops I mistook it for "Project" management. For such a certification in Product management you could check out Coursera's Brand management course: https://www.coursera.org/learn/brand
Actually with Project management the case is a bit different. There is a central body called "Project management institute". They have a selected number of certification options that are recognized globally. You can defnitely attend free courses but only PMI can certify you to be certified Project Management Professional.
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