how to make my own custom page for qtdragon_hd?

I'll add it to docs but here should help:
github.com/LinuxCNC/linuxcnc/blob/master...b/keybindings.py#L34

use the quoted text.
 

Is there any tutorial how to add buttons-leds-selectors in qtdragon_hd ?

you mean buttons with indicator leds?
In designer:
select a HAL button or linuxcnc action button.
Look under properties for IndicatedPushButton
then set
indicator option: true (you should then see the led)
It will now reflect button state (if it is a checkable button)

If you want to control the led by a HAL pin then:
indicator_hal_pin_option property: true

If you want it controlled by linuxcnc status.
indicator_status_option property: true
set an 'is_SOMETHING_status property true

shape_option
on_color
off_color
circle_diameter (for round LEDS)
indicator size (for tri angle Leds)
width and height (for bar Leds)
right_edge_offset (moves LED to the left by pixels)
Top_edge_offset (moves LED down by pixels)

I think that's it in 2.9. In master you can flash the indicators too.

In qtdragon_hd left to red mushroom estop button has a list with upto 10 macro buttons
that execute the commands from ini file [MDI_COMMAND_LIST].
How can i change this behavior and config these buttons to set value (true/false) of hal pins? For example one button to enable machine light.
Can i put in this vertical bar except of macro buttons some led indicators ?
Is there a language file for translation of menus ? How can translate it ?

Do you use macro buttons?
There is no default option to add widgets there, but i may be able to add a small customization. o you want it to show like the macro buttons is if it shows basically all the time, is that ok?
Of course you can always use designer to add widgets there and save it as a custom ui file.
The disadvantage is if qtdragon gets updated you might not get the updates.

unfortunately I have not worked on translation code for qtdragon.
I'll have to speak with the Qtplasmac to see what they did.

Yes i want to show all the time the buttons like macro buttons but not execute mdi commands.
I want these buttons to set hal pins true or false for example set gears position in gearbox, open machine light, clamp tool, select active spindle 1 or 2 spindle from 2 spindles  have the machine ..

I am struggling a bit on finding an 'easy' way to do this with a custom add on.
In the mean time -how many LEDs and buttons do you want? Labels?
I will make a custom ui file for you, to get you going.