Is it possible to create an inhibition against some activities? There is an unexplained psychological reason that causes one not to be able to do some random activities (for instance, not being able to eat several days because one's mouth just won't open to take in food or they can not go out to ride a bike because, as much as they want to, it's like their body refuses them to dress and step outside).

There are more examples how the problem occurs but I really want to know what is the psychological reason behind it (I know it isn't anxiety). The problem occurs at random times and against random activities that are a part of one's everyday life.

Also I'm intrested in whether or not an inihbition can be psychologically created by choice against some bad habits (for example it could be the saviour of the people who are trying to quit smoking if, however bad they want to smoke, their hands just won't take a cigarette).
There is an answer to the first part of your question here:  What causes behavioural inhibition? 

I am answering this part of your question:
I'm interested in whether or not an inhibition can be psychologically created by choice against some bad habits (for example it could be the saviour of the people who are trying to quit smoking if, however bad they want to smoke, their hands just won't take a cigarette). 

To induce inhibitory behaviour requires the use of negative reinforcement. To avoid punishment, or discomfort, an individual will learn to avoid a particular behaviour.

In the case of addiction (as mentioned in your example with cigarettes), the issue is:   Creating a negative reinforcement that causes greater   discomfort (referred to as negative affect in the article below) when using the drug, as opposed to the discomfort that results from abstinence.
The same can be drawn for behaviour payoffs. If a certain behaviour alleviates for example, anxiety, then the discomfort of the negative enforcement will need to be greater than the anxiety the individual is avoiding.
As one can imagine, it is not always easy to create a humane punishment that creates a discomfort greater than the what the individual seeks to avoid.


  This article offers a reformulation of the negative reinforcement
  model of drug addiction and proposes that the escape and avoidance of
  negative affect is the prepotent motive for addictive drug use. The
  authors posit that negative affect is the motivational core of the
  withdrawal syndrome and argue that, through repeated cycles of drug
  use and withdrawal, addicted organisms learn to detect interoceptive
  cues of negative affect preconsciously. Thus, the motivational basis
  of much drug use is opaque and tends not to reflect cognitive control.
  When either stressors or abstinence causes negative affect to grow and
  enter consciousness, increasing negative affect biases information
  processing in ways that promote renewed drug administration. After
  explicating their model, the authors address previous critiques of
  negative reinforcement models in light of their reformulation and
  review predictions generated by their model. (PsycINFO Database Record
  (c) 2012 APA, all rights reserved) 1



 1 Addiction Motivation Reformulated: An Affective Processing Model of Negative Reinforcement.
Baker, Timothy B.; Piper, Megan E.; McCarthy, Danielle E.; Majeskie, Matthew R.; Fiore, Michael C.
Psychological Review, Vol 111(1), Jan 2004, 33-51. doi: 10.1037/0033-295X.111.1.33