Hello,
Its nice to see you have an interest in real world flying. Prices to get a liscence can vary, depending on several things such as landing fees if applicable, price of aviation fuel, and the behind the stage charges from your flight school. You can expect the private liscence to be around $5000+. But of course, it depends on where you are, and can be lower or higher.
How much does it cost for a plane? Well... I don't own one, and Im not sure I will for quite some time. I remember seeing a 172 for 200000 ish. And it costs a lot to maintain aircraft according to the law as well. But you dont have to own a plane to fly for fun

To be an airline pilot, you do not need to be in the air force. Air force experience helps because you get your share of airtime as well, and its an economical way of doing it. Just have to balance your lifestyle with money on that one. I believe that once you get your Airline transport pilot liscence, which is thousands of hours away, you can start flying the larger aircraft

Hope this answers your questions :)
Oh by the way, even though I never started early, I think when your around 15-16ish you can start learning to fly if you want, won't be getting your liscence right away but you can get some hours if you want to put some money into it.
