are there many walking trails, like 3,4 hours walk

Yes many to choose from

Yes

There is a lot of trails and it is a great place to stay

Yes there are many. Use this map to help you choose. Remember, some are a loop, some require a vehicle parked at the entrance and exit. http://www.wnytrails.com/AlleganyStatePark/AlleganyStateParkGuideMap.png