How to tell them ?

You don't have a problem, you're shy and maybe verbal just isn't your thing.
It can be difficult to explain in full what anarchy really means to the average person. Its not that your shy, its that sometimes people just don't want to listen or have pre-existing ideas of what anarchy is and don't want to expect what you have to say.
First, remember that most when most people think of anarchy, they don't think of a form of government, they think of people breaking into stores, cars flipped over, etc. They think its just pure chaos and they have a hard time excepting it as anything but pandaemonium
When people ask you what's wrong with capitalism or religion, just tell them. You sound like a coherent, intelligent kid, just start off with a big picture answer and use examples that they'll understand (i.e-nike). If they follow you then get into more detailed examples. If they laugh at you, fuck them. I know a lot of people who are more liberal and hip then thou and they always say that i'm wrong and find some p.c answer, it pisses me off but at least i tried to explain it to them.
I guess I'm pretty shy too, and its sometimes a challenge just to talk to new people. If they ask me about my beliefs or they say something I know is wrong, i just take a deep breath and say it in a level headed manner and explain as best i can.
Hope this helps a little

 

You really got no problem at all, it's just your age with it's lack of experience, I think you're a smart and observingly/mindful youth - but you won't stay a youth for ever. Just take the time to make your experiences and the shyness will wear off just because you're getting older and more used to express yourself - so don't worry!
Doing the band thing is a good start and the feeling/doubts just before the first gig are scary for everyone including me (I don't want to remember my wet pants...) but you will get used to it.
If the discussion thing is that important to you just try to continue doing it, it needs some experience and practice, keep on thinking about stuff you're interested in and make up your mind. Reading might help also, getting information about actual important things, most people will respond easier if you talk about things they know too, its easier to understand the big abstract matters if you try to explain in "every day" examples...

the other thing:
Using the computer or internet doesn't mean that the repressive way capitalism is abusing the technology to exploit, sedate, distract and control people is not obvious to you.
The problem is not the product itself, the problem is how it's produced and how it's used and I'm sure that computers and internet will not be abolished because capitalism will be abolished.
Your personal property (like guitar and laptop) is not a direct tool to do things the way capitalism is doing them, so there is nothing wrong with it, just try to avoid blind consum habits like coce, nike and the like.
Private property like production facilities or claimed land can be used to get an advantage over/of the needs of other people, and capitalism means that private property must be used to exploit people - you see the difference between private - personal property?

So don't worry and give yourself the time to grow up and getting used to yourself - I think you're really promising... good luck!

 

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