Is there a way to buy or really otherwise obtain their operating system and/or browser? I have clicked around, and I read a lot of enthusiastic descriptions, b

Is there a way to buy or really otherwise obtain their operating system and/or browser? I have clicked around, and I read a lot of enthusiastic descriptions, but how does one use it? Is it only available if you buy the computer, they have designed which you can't buy? I feel like I have clicked around in circles several times without gaining an understanding of how or when it was possible to use them?