Air Training Corps or anything subsidised by the RAF as mentioned above by Lost In Cloud is a good start, lots of kids get to march up and down, push gliders, and occasionally fly; the University squadrons are excellent value if you qualify. After learning the basics on one of these programmes, often life paths go different ways, the kid has to get a proper job, raise a family, move round the country, change wives, whatever, and then, at the age of 50 plus, they COME BACK TO GLIDING.....and already know basically how to fly!
Other chaps go on and mortgage their future to buy a commercial rating, this is a very stressful path but you might find yourself in the sharp end of a Boeing or an Airbus .... or meat bombing....
As for going on glider pilot net, not a very useful forum because it is poorly designed and hard to read - and full of immature young persons.....
PPRuNe enjoys the patronage of pilots and those interested in aviation who can actually communicate facts, ideas,....and scornful putdowns