What is the probability that there is another earth like planet in the universe?
"like" the earth, if you mean by that same size as that of the Earth, orbiting around a star, there are probably lots of planets.
But if you mean by same that there should be life on it, well we don't know what it takes to get life to appear given favorable temperature conditions and the presence of required molecules. The experiments of Miller in 1952 only proved that amino-acids could emerge under the right circumstances. But not life. Close, but no cigar.