I don't believe that a perpetual motion machines PMM exists, although I've seen videos on YouTube of people who have claimed to create PMMs. It fundamentally impossible to create one simply because of the fact that to create one would be to break one if not all the laws of thermodynamics.
First this first, the first law states that energy can never be created nor destroyed, but it can only be converted from one form to another.
Energy input = Energy output
So for a machine to move forever, then all the energy that starts it's movement must not only do that, it must also keep it moving. If that was possible then maybe we'd be able to make a PMM.
Theoretically speaking, even if we could somehow circumvent the first law, the second one is iron clad. It states that the entropy of an isolated system can never decrease over time. In the case of PMM what it's trying to say is that no matter how efficient the system is, some parts of the energy will escape due to the interaction of the machine with external forces like wind and moving parts which in turn will build up friction and that will end up creating heat. Thus, the heat created will lead to energy loss and if all the energy that was used to make the machine move isn't available, then it will inevitably stop moving eventually.
It's just not possible, at least not right now.