How to purchase sui?

Could you please explain the process of purchasing Sui? I'm quite interested in investing in cryptocurrencies but I'm not sure where to start with Sui. Is it available on major exchanges? What kind of wallet do I need to store it securely? Are there any specific steps I should follow to ensure a smooth transaction? Also, is there any advice you could give me on managing my Sui holdings in the long run? I'd appreciate any insights you can provide.