@arjunmisra1994 At some point this dog has received a payoff for stealing or counter surfing. If you want to get this under control two things need to happen immediately. Put stuff away - particularly things that have the human scent on them and always put food away.
Do this consistently and you have half the job done.
Next, continue to reinforce 'leave it' and reward highly with something the dog cannot resist. Repeat this frequently. Same goes for 'down'.
'Drop it' needs to happen because he is stealing but perhaps make that command lots more fun by training 'trade up' This means give the dog something to hold in his mouth (train this if you have not) then 'trade up' to a treat. Use the dogs toys and repeat until the dog will happily hand over anything to you for that treat.
Please remember that the more the dog does something, the more likely he will continue to do it. So to stop the behaviour you must not have any incentive on the benches, tables or any horizontal surface that would provide a pay off for him.
Your dog is an adolescent, he will quickly try new things out and anything that gives him satisfaction whether it is attention, taste, smell or a good chew feel - are likely to encourage him.
Keep a lead on the dog for him to drag around the house whilst you are working on this, it makes it easier to guide him away from the problem and it also psychologically reduces the dogs sense of freedom.
Close down most of the house and ensure that the dog is supervised at all times until he passes through this stage.
Make sure you have all the family onboard about this or it will become an established habit.
I know of situations where one family member did not shut their door or put their stuff away and the dog left all of the other family stuff alone and always went for that persons stuff. Dogs are incredibly smart and will go the route of least resistance. Everyone in the family must be consistent in the way this is being dealt with.
Make the kitchen a 'no go zone' for your dog anyway. Dogs and hot stuff do not go well. Train the dog to go to his bed where he can watch but not wander into the food prep area. Lure him to his bed and treat. Train a command for him to exit his bed and reward. Do not let him just wander off.
Do not allow stalking, begging, being fed human food or scavenging. All will give the dog the sense that it should continue to take and exploit opportunities with human food and things that smell like their humans eg remotes, phones, socks, bags, shoes etc
Good luck.
