there's just an infinite amount of mass and energy that always existed and acts and reacts according to awesomely beautiful laws that work in harmony to give us the physical reality we can see all around us.
It had a beginning, of course. There is no such thing as a perpetual motion machine and the earth is still moving at more than 1.3 million miles per hour.
https://www.revimage.org/how-fast-is-the-earth-moving-in-mph/