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We often do things differently in north America -- like using feet and inches, and our building codes are sometimes different.

Attics usually have intruding roof planes, but your floor plan does not show any.

That seems like a ton of wasted space. I would move the bathroom down by the storage area and put a good sized closed in between. That way you can use those big windows to provide more light to the bedroom.

In am confused as to the actaul floor spce and ceiling heights this just looks like a 2nd floor of a house not an attic IMO. 2M head height is a bit low but maybe post some pics of the space .Normally moving btahrooms is tricky so a bit more info about exactly if this is renovation or a new buld

To do any if this, you will have to completely change how the home is insulated and vapor sealed, to a ”hot roof” system. An unvented attic assembly. You can not do it with a traditional vented roof system.