I love reading, and I also write at times but now that I want to get serious with writing every time I get a pen I end up writing nothing though I have ideas!

If you want to be a writer, you need to start writing every day, even if it's just one sentence. Different writers write in different ways - you can come up with a detailed story line before beginning to write, or you can just start writing, and see where your writing takes you. You can even start writing out of order from the middle or the end of the story! Don't worry about writing badly - you can always go back and fix things later.