@hansmex Unfortunately the one of those two "rooms" is the hallway of the flats main entrance if I'm reading the underlying background image right. It would also have no natural light.
@Shmenosan Hansmex is right, but I'll add that depending on how the block of apartments are contructed, there are dedicated channels vertically through the whole building for water and waste handling beyond that northern wall that also services flats above/below yours too. It would be impossible to move the kitchen to the living room, as you couldn't have your kitchen waste pipes descending into the downstairs neighbours living room.
As Dorin said, you created this plan from some funky looking underlying drawings so it is hard to know how accurate your plan is. Any ideas would depend on the ability to squeeze things in, so accuracy is paramount.
You might be able to rob space from the living room, the master bedroom, and the central hallway, and come up with two small bedrooms where the 2nd bedroom currently is. Your problem there is getting natural light into all of the bedrooms. You might be able to split the 2nd bedroom window in two, but I'm guessing moving or adding new windows is very unlikely. It also means the second and third bedrooms will be small and not have great light levels.
My question is why do you need 3 bedrooms? Is BR3 to act as a small office? Is it so two children have their own rooms? Or are there more than 2 children?
Are you trying to have an occasional guest room? There are inventive things you can do here, but more info is needed about number of adults/children and usage.For example if you wanted a room each for two kids you could use a bunk bed like arrangement, but built in to the dividing wall so one bed is in each room. This would save a heap of floorspace. Here's an image that gives you an idea of what I mean: https://www.pinterest.co.uk/pin/779826491704278186/
