If i own a 2000 jeep wrangler CJ and its stock but i want to make it a good offroad vehicle what do i buy?

You should put in on Ebay. Because there is no such thing as a 2000 Wrangler CJ. The last CJ was made in 1986. If you put all that stuff on your Jeep it should do ok, don't need to go with 4.88 gears. 4.56 will be fine. Probably don't need to regear unless you go with 35'' tires.