A job application letter should be more formal and business-like. I would leave your first paragraph off (the self-introduction). Those are things you will discuss in the interview.
Under "Work Experience" do not mention that you were bored, or that you didn't perform the job very well. You should only make positive statements when applying for a job.
Instead of "vehicles register" say "vehicle registration." Instead of "to indicate people where some departments of the hospital are," say "informing, assisting and directing patients and visitors as necessary."
Instead of "I think I am a responsible person" or "I think I can do a good job", make positive statements. "I am a reponsible person and am confident that I can do a good job."
I don't think you need to mention liking your colleagues or lunching with them. Save that information for the interview.
Instead of "on-time" say "punctual."