How to train dog to pee out side ?

Hi Rohit, How long has this dog been with you? If he has been with you since he was a puppy he should have been trained in this by now. It's impossible for him to relieve only when he's taken out. you said you take him out twice a day. Do you expect him to relieve only twice a day? Do you thing that's feasible? Do we go potty just twice a day ? That's it?I'm sure no is the answeer! So we can't expect even the dog to relieve only twice a day when he's taken out. He have to do his daily business when he's in.
Scolding is perhaps the only reason why you've not been able to potty train the dog. This just make the matter worse. What you first need to decide is the place in your house where you want him to relieve. Place some newspaper on the surface of that place. Encourage the dog to pee there. You can place a cloth soaked with his urine on that place so that the smell can encourage him to pee there. Be patient! Take him there as often as possible, like when he's had his food, when he has come back from a walk or after he has comeback from play sessions. The dog will eventually pee there. When he does that, praise him by saying great job!!Give him he's favourite treat!! That's it. Dogs are animals of habbit they'll do what you tell them to do. He's not been able to learn this because we never inculcate this habbit right from the day you brought him in!!And remember dogs are very clean animals, even they hate to keep their surrondings filthy but being a responsible owner you have to guide him through!
If you still need any assistance, let me know.

If i am not mistaken , your dog is a male, hes try to mark his territory. At some place, he started having a feeling of threatened , so what is try to do is not urinating actually hes marking the territory.

Make him feel home, dont let him feel hes the alpha dog of the pack, sometime certain male dogs do this, try to show the dominance , show him whos the master. To start with try giving him less water, take him out immediately after giving him food and water, take him for a long walk (like 20-30 Mins).

As far as training dogs are concerned you need to be consistant and regular, slowly they will start responding.

Hope this helps