In case you are new towards buying NFTs in OpenSea, here are some videos to help you get started.
Here are some references on the terms mentioned in the videos:
1. Metamask - This is your wallet to store your cryptos and NFTs.
2. Ethereum - Ethereum is a crypto coin and it's the "currency" use to buy NFTs in OpenSea.
3. OpenSea - OpenSea is whe website to purchase the NFT. Think of it like the "eBay for NFTs".