Thanks Pablo 
for workable solutions. Both solutions are working, as I imagined.
Anyway, fortunately I do not work with Word itself, but for example. Colleagues, friends and acquaintances. It is sometimes necessary make something  in ConTeXt when Word is not enough on it. So fortunately there is no condemnation to me, but to someone else:-).

Greeting Jaroslav Hajtmar

From: "ntg-context" ntg-context-bounces@ntg.nl
To: "mailing list for ConTeXt users" ntg-context@ntg.nl
Cc:
Date: Sat, 18 Apr 2015 09:23:51 +0200
Subject: Re: [NTG-context] Hidden chapter header? ... was: Change counter of chapters

> On 04/18/2015 07:22 AM, Jaroslav Hajtmar wrote:
> > Hello ConTeXist
> > My last Subject contribution maybe so misleading that it nobody react.
> > I'll try therefore to bring different view:
> > Exist any possibility of creating some kind of hidden chapters
> > (sections, subsections)?
> > The command would increase the counter of chapters (sections,
> > subsections). Maybe it seems as rape of ConTeXt, but in certain moments
> > this option would help me.
> > In my case it is the integration of practical part of project (worked in
> > ConTeXt) into Word project:-(...
> >
> > For example I need to start writing any text from 53 page and such from
> > the 5th chapter (or section).
> > It is possible in a similar way as I set the start page number set also
> > the counter of chapters (sections)?
>
> Hi Jaroslav,
>
> adding the following commands before \startext does the work:
>
> \definehead[hiddenchapter][chapter]
> \setuphead[hiddenchapter][placehead=no]
>
> But there is a proper way to set the chapter number:
>
> \setupheadnumber[chapter][56] % +2 or -5 also accepted
>
> By the way, going from ConTeXt to Word you know you are on the road to
> perdition, don’t you? ;-)
>
> I hope it helps,
>
>
> Pablo
>
>
>
> > Here is my minimal example:
> >
> > \starttext
> > %\hiddenchapter{Fictive chapter}
> > %\hiddenchapter{Fictive chapter}
> > %\hiddenchapter{Fictive chapter}
> > %\hiddenchapter{Fictive chapter}
> >
> > \page
> >
> > \setcounter[userpage][53]
> >
> > \chapter{Fifth (actually first) nonfictive chapter}
> >
> > blablabla
> >
> > \stoptext
>
>
> --
> http://www.ousia.tk
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