i recommend you to watch this list of videos that will explain Bitcoin and Blockchain so that you will definitely understand it more - https://www.youtube.com/watch?v=LszOt51OjXU&list=PLwLWZsWocr0lE64ImcrvP1aJtXuSXPtTX
or if you are from Czech Republic or Slovakia i highly recommend you to watch this list of videos - https://www.youtube.com/watch?v=Z92ADb5i42s&list=PLiD1OrtvRy70RQ8k5HH0E3vHQPpEIJJhZ
We store our bitcoin in : https://trezor.io/