No stuck for idea but I want to break my entrance wall and I am stuck because of the fire regulation...what can I do apart sprinklers which is very expensive I imagine? someone know? All the best...

I'd look for a different flat with easier access to the garden. Too big a risk to buy it then talk about a "fire escape" which is probably not required or there would already be one.

I agree that you ground floor flats you should be able to escape through a window if there in a kitchen fire between your bedroom and the front door. There are however guidelines about window apertures for this purpose and it may be that your current windows may have too small an aperture or it might be too high to easily get out of. Personally I would be requesting a site visit from building control since their advice three years ago led to you being in this situation. I would be looking for them to explicitly give you your options to resolve this and it might be that there are several possible solutions.

Jen P makes the point which is part of what I think some of us are concerned about which is too many doors in a normal sized room make it hard to have necessary furniture like sofas which is the function of a living space. The hall door is near the kitchen opening and if there was a part glazed partition where the double doors are it would still “connected” I think whilst still allowing furniture in the room. If you are set on access from kitchen though another idea could be to have two openings either side of a solid wall, that way I think there are more options for furniture placement?? If doors are necessary sliding doors moving across the the middle section wouldn’t get in the way. And if you block the hall door maybe recess a bookcase for interest in the hall??