Expanding Universe, but the speed of its expansion is a mystery

Light from some stars take millions of years to reach earth creating problems for scientists to measure the speed

It is very easy to measure speed of something in earth. We calculate the speed by estimating the time required for an object to reach some distance. But measuring the speed of universe is totally different. As light from some star takes millions of years to reach earth, by the time it reaches here the star may have long gone. And we cannot tell the distances it travelled with certainty as it is too far. So measuring the speed is a huge problem for the scientists.

Is there no way to find the speed of our universe?