A cryptocurrency Wallet is used to manage, sent and receive cryptocurrency holdings. There are different types of Wallets with different levels of security such as desktop wallets, mobile wallets, hardware wallets or paper wallets.
Wallets do not actually store cryptocurrencies per se, but the private keys to access the digital assets on the blockchain.
For this reason, it is critically important that you keep your private key and seed phrase safe and never share them with anyone. Once someone gets hold of your private key, that person will also be able to access your crypto assets stored in your wallet!
For this reason, a well-known saying in the crypto world is: Not your keys, not your coins!