Where can I buy $stx?

Excuse me, could you please clarify for me where I can go to purchase the cryptocurrency known as $STX? I've been hearing a lot about it and I'm interested in adding it to my portfolio, but I'm not sure which platforms or exchanges support its trading. Would you happen to know of any reputable exchanges that offer $STX for purchase, or any other methods I could use to acquire it? Thank you in advance for your assistance.