In the book Jurassic Park (later turned into a movie) author Michael Crichton describes a formula to bring dinosaurs back to life after 65 million years of extinction. There are 6 steps to this Jurassic Park Theory. The first step is to find a piece of amber with a blood sucking insect from the dinosaur trapped in it. Amber is a fossilized tree sap. Usually it is clear with a yellowish tint. Sometimes insects are trapped in the tree sap before it hardens. Some amber dates from the Mesozoic Era when the dinosaurs lived and it is not impossible insects, carrying dinosaur blood, might be trapped in amber. Amber preserves the soft tissue of an animal for vast amounts of time. But this step costs considerable amount of time and money to find the right piece of amber.
Step two is to extract the blood that the insect sucked from the dinosaur. It is not unreasonable that we might be able to extract some dino DNA from the blood cells we recover. After that, though, we run into trouble. Scientists have already extracted DNA fragments from an extinct weevil that was trapped in amber for up to 135 million years. And there was only a fragment of DNA of the weevil and not the blood of something it bit.
The next two steps are where things get really difficult. Step three is to use the dinosaurs DNA found in the blood cells as blueprints for another dinosaur. If the piece of the DNA is missing, fill in the gaps with frog DNA. Step four uses these blueprints to create a dinosaur egg. DNA is often likened to a software program on a computer because it contains instructions on how to build a living creature. To do something on the computer you need not only the software, but also the actual hardware to run it. In the same way, we are missing the hardware needed to execute the DNA. This would normally be a female dinosaur that produces an egg with DNA in it. Unfortunately, not any chicken egg will do it. We need a dinosaur egg with the same species we are trying to duplicate, that my friend's is hard to do.