Why am I not improving?

Thank you everyone for taking the time to help me.
Now for something to say,

I sometimes get completely baffled when opponent don't plays the move I am expecting, like after
1.e4 e5 2.Nf3 Nc3 3.Bc4
now I expect him to play either Bc5 or Nf6, but instead opponent plays something like f6 or Qf6 or d6, now i am aware of the fact that he is not doing it right, but i don't know how to react or take advantage of it. I also get demoralized when opponent plays anything else than e5 in reply of e4, and sometimes opponents play absolutely strange moves like (g6, f6) etc in the opening leaving me with no clue what to do,
I completely suck when i play with black, anything other than e4 from white makes me feel that i am not going to have a good game.
In the game shared by @jonesmh I underestimated the opponent and wasn't attentive.
Another thing, when I keep losing I keep playing and keep losing, sometimes I lose 150 rating point like this on a day and the next day when I play with a fresh mind again I gain back my ratings.

I have noticed that most of the repliers are above 1700, that means I am well out of your leagues, now i would like ask you guys are you all naturally gifted or become good through practice? I mean is it practically possible to reach 1700 through practice?

Of course it is possible to reach 1700 through practice.
If you lose a game, stop and analyse it before you play again.
The stockfish analysis and the learn from your mistakes features are great. Never ever underestimate an opponent always stay attentive.
If your opponent plays a move you do not expect, then think. Always play to develop pieces and to control the centre. In all the examples you give above the right reply is d4: centre, develop bishop c1.

Stop thinking players above 1600 are gods. We are amateur players. To be really honest, we are all bad players. I saw one of your games. You simply dropped three pawns with no compensation. If you do that, you lose. It is as simple as that. So stop dropping things. If you do that, and nothing else, your rating will rise 100 points or even more. That's a good start. And choose longer time controls, always with increment (15 + 10, at least), so you can look at the board and not drop stuff. Good luck.

Besides coaches, there are lots of books and videos that teach chess. Theory is important, but without a chance to practice your theory it gets forgotten. Repeating the same errors, is not going to help your chess. A map might show you the roads to move north, but in chess there are not road maps that tell you the alternate routes to make it to victory. Chess principles and chess methods will guide you in a winning direction.

At your level, your main aim should be to prevent your opponent pieces from overlooking or entering your territory.

That alone will help you improve.

There is a difference between a wrestle and a battle. It's only a wrestle, if you use one piece without support from others. You will win battles if you coordinate your pieces as a brigade. Learning to platoon your pieces becomes an art that can be learned by softwares.

A software like Lucas Chess can help chess players learn lots of essential moves by practicing them. One part of the software that I like is the training positions, that practice tactics by repetition.