Can I buy AVAX on MetaMask?

Can you please explain to me in detail how I can purchase AVAX using MetaMask? I'm a bit new to the cryptocurrency world and am trying to understand the process. Is it possible to directly buy AVAX tokens through MetaMask, or do I need to go through another platform first? Also, are there any specific steps or considerations I should be aware of when making such a purchase? Thank you for your help in clarifying this matter for me.