Can Anyone Help Advice Needed Plz

I have recently bought a MK1 GOLF E reg cab, there is an electrical fuel pump and an mechcanical fuel pump. Why has this car got 2 pumps when surley it only needs one on a carb, engine size is 1.8 . Maybe i'm wrong but i ve never had a golf with 2 pumps, but on all my other golfs i ve never have this problem.. also the carburetor floods and when the car does start its only on one cylinder.
Any help greatly apprec,