Choosing your distribution isn't that hard. You simply look around a little bit for something that you consider cool. But remember don't start with something to hard.Because you are probably new to linux here is my recomendation:
- If you are currently Windows user I would recommend you Linux Mint. It's known for being easy for new Linux users that were using Windows earlier. It is realy simmilar to Winows overall. Here you can download it.
- If you are on the Mac right now good option for you will be Elementary OS. Here is link to it's website
- If you are using Android and you want to jump into PC Endless OS is great choice. Here you can find it.