MetaMask is capable of holding, sending, and minting NFTs.
There are, however, some minor differences between MetaMask Mobile and Extension when interacting with NFTs: on MetaMask Mobile, you can see your NFTs in-app, while on the extension you cannot see them natively.
The best way MetaMask offers of viewing your NFTs is currently in MetaMask Portfolio, available at portfolio.metamask.io. All you need to do is connect your wallet, and your NFTs should be viewable. Easy!
Alternatively, third party websites such as Etherscan, OpenSea or Rarible may enable you to view NFTs.