A standard UK PPL is effectively type rated for Single Engine Piston (SEP) aircraft.
In order to fly multi engine you must do the ME course and in order to fly jets you must obtain a jet rating.
Equally the PPL only allows you to fly Visual Flight Rules (VFR) and an Instrument Rating (IR) must be obtained in order to fly IFR.
If you want to fly a 747 VFR you are a braver man than me.