I am a bit intimidated at the thought of navigating all that complex and tightly controlled airspace.
With good cause, Britain's airspace is a complicated mess - and I say that having held a licence here for over thirty years and am very used to it.
The vast majority of us nowadays rely on apps to manage navigation and airspace avoidance, in addition to the traditional chart and navigation methods. Skydemon isn't the only choice but is definitely the most popular and well worth a look at.
Our ATC is indeed quite non standard. But it does make reasonable sense once you're used to it and our "listening squawk" system de-stresses it a lot. The CAA's RT and VFR flight guides are free online and well written. Those will help you a lot.
G