I am wildlife content writer its my passion to write about wildlife flora and fauna. I need to know which wildlife should be best from delhi. it should be Jim Corbett National Park Or Ranthambore Wildlife Park?

Both parks are very different. One is in the Himalayan foothills, the other in the semi-arid region of Rajasthan. The flora & fauna are also very different. Ranthambhore is predominantly acacia, while the Corbett is more of Sal, shisham, Runi, Bargad, Tun and coniferous up on the hills. There is better diversity in Corbett.
If you are tigerwallah than it is Ranthambhore but if, as you mention, you wish to write on flora/fauna, it is definitely the Corbett! However, to get a grip of the subject on your hand, you must stay inside the park for a couple of nights atleast, though the accommodation is basic.
The morning train to Kathgodam will fetch you to about an hours drive to the Corbett, through pristine country.
Happy hunting!

Thanks so much for very good information. i have booked my tour for jim corbett national park On coming 8th November to 10th November. booked my safari with the Official Website of Jim Corbett.