NFTs generally follow property rules, with wrinkles
NFTs are, at the classification level, generally subject to the same property-based logic as other crypto assets: minting, buying, and selling can each trigger tax consequences depending on the specific circumstances. Buying an NFT with ETH is, from the ETH side, a disposal of ETH at whatever it's currently worth versus your ETH cost basis — the same logic as any other crypto-for-crypto trade. Later selling that NFT is evaluated as a disposal of the NFT itself, comparing the sale proceeds to what you paid (its cost basis, generally the value of what you gave up to acquire it, including any fees).
Where NFTs add wrinkles is in how they're often categorized once you dig past the basic disposal logic. Some jurisdictions apply different capital gains treatment to assets categorized as 'collectibles' compared to more generic property, and there's genuine variation in whether and how NFTs get pulled into collectibles-style rules versus treated like any other digital asset. This is very jurisdiction-specific and evolving, so it's an area worth explicitly checking current guidance for rather than assuming NFTs are taxed identically to fungible tokens in every respect.