An 8'x8' kitchen is a classic deadend galley style kitchen. Option A is to locate the refrigerator adjacent to the center doorway, stove with exhaust hood in the middle of the dead end end wall, sink in the center of the wall opposite the refrigerator. LOGIC: Classic triangular work relationship, plenty of counter workspace, easy access to refrigerator for others without interfering with someone cooking at the stove, space on each side of the sink for a dishrack. Option B really can't beat Option A unless your building's plumbing wall dictates other locations for your sink and stove. Is there a window in the kitchen? This can also have impact on the layout.

Something like this may work. Note the changed door positions so that anyone in the bedrooms can visit the bathroom without disturbing anyone else in the lounge !

It would be helpful if you share the layout of place.

I disagree with the advice above, the bathroom door that is in the passage should be closed. The reason for this is that you already have a bedroom without an attached bathroom. If you go by the advice above you will then have two bedrooms without an attached bathroom. Its not ideal. Also, you havent told us for which uses are the other two bedrooms. Are there going to be old parents in the bedroom with the bathroom or kids or are you going to use this as a guest bedroom? If you close the door in the passage you can have a bigger vanity by moving the WC behind the door that is from the bedroom side. This is also good because you should never have a bathroom door with a view of the WC. The WC is a very private spot and there shouldnt be a direct view of it from the room. Also we tend to spend more time sitting on the potty than washing hands, looking at ourselves or taking a bath. Once you move the WC you can have the vanity extending till the wall and will be 2.5x bigger than what you currently have.