Where can I buy NFT?

I'm curious about investing in Non-Fungible Tokens (NFTs) but I'm not sure where to start. Could you please guide me on where I can buy NFTs? I've heard about various platforms but I'm looking for one that is secure, has a user-friendly interface, and offers a diverse range of NFTs to choose from. Also, are there any specific requirements or steps I need to follow to successfully purchase an NFT? It would be great if you could provide some insight into the process and recommend a trusted platform.