If rivers flow from land and into the ocean, then where does that water come from?

Question

I’m essentially asking how a river “starts”, since I generally know that rivers mostly ends flowing into the ocean.

If you could, please use the Yangtze river as an example.

In: Physics

Answer 1

Water evaporates from the oceans, becomes clouds, which drifts over the mountains and falls on the mountains as snow.

In the spring and summer, the snow melts and becomes streams which become rivers which eventually flow into the oceans and the cycle repeats itself ad infinitum.