Simulate push button with arduino

Carlcox89:
So, the (**) is a 2N1000 transistor ?

No, 2N7000.

Carlcox89:
and A connects to actual mode button (top pins), that works like 3.3v and when pressed goes to 0v, correct?

And (*) can be any NPN transistor like 1N4148?
and B is connected to actual powerbutton (bottom pins) connected to collector and top pins to emitter, so that when i set HIGH it's like pressing the button, right?

Yes, except that 1N4148 isn't a transistor, it's a diode. Any small signal NPN transistor will do.