Hi Mark, welcome
A few things can cause those symptoms on MK6 Golfs, especially the hesitation when accelerating and popping when blipping the throttle in neutral.
Common possibilities include:
Coil pack or spark plug issues – Very common on VW petrol engines. A weak coil or worn plug can cause hesitation under load and popping from unburnt fuel. Usually not expensive.
MAF (mass air flow) sensor – If it’s dirty or failing, the engine won’t fuel correctly, leading to laggy acceleration.
Vacuum leak / split hose – Cracked PCV hoses or vacuum lines can cause delayed throttle response and popping.
Throttle body / carbon build-up – Especially if it’s a petrol engine and hasn’t been cleaned in a while.
DSG-related hesitation (if automatic) – Sometimes feels like engine lag but is actually gearbox response.
First thing I’d recommend is getting the car plugged in for fault codes, even if there’s no engine management light on. That usually points you in the right direction straight away.
It would really help if you could tell us which model MK6 you got?
Most of the above are fairly inexpensive fixes if caught early, so don’t panic just yet.