I have a query about the study of fossils (palaeontology). Let me know about the study of fossils. How do biologist discover "DNA" information from dead and old fossils such as a dinosaur? (answer this question in a paragraph or two)
How biologist discover "DNA" informations from dead and oldest fossils such as dinosaur.
They don't. In general fossils contain very little organic material. It's all been replaced by stone (silicates). On top of that DNA degrades over time.
There have been a handful of cases where researchers have claimed to recover small fragments of DNA from dinosaur fossils, but these are disputed, and are generally thought to be the result of contamination with human or other modern DNA.
DNA has been recovered from some more recent fossils like Neanderthal. For such a general question a better starting place would be to read the Wikipedia article on Ancient DNA.