Let's talk about the basics of a smart contract.
Web3 is open, decentralised and built on the blockchain using smart contracts. Smart contracts are decisions written into code. If you are a non-technical user, use steps below to understand a smart contract.
Find the contracts public address
Every smart contract has a public address.
Anyone can access and read a smart contract using the contracts public address using website like Etherscan. For example, this is the contract for the Bored Ape Yacht Club NFT series.
Supply and holders
The tracker tab shows you the total supply of the token and its value.
The address is available under the "information" section on OpenSea. As of writing, there are 10,000 BAYC tokens in circulation. There are 6,105 token holders. It's been transferred ~55,000 times.
Distribution of holders
The holders tab shows you who holds the token and in what proportion.
Dingaling.eth holds 105 Bored Apes. There's a handy piechart that shows that the top 100 holders collectively own 18.97% of BAYCs.
Contract
The contracts tab allows you to read actual code.
Etherscan summarises the key parts of the contract for you if you click "read contract". Look at the total supply (10k for BAYC), type of token (ERC721) and the symbol (BAYC). If the contract is on Ethereum, the token will usually be ERC721 (NFT) or ERC20/ERC777 (fungible).
To close
Anyone can look up a smart contract. Look up the basics of any contract that you are buying into. Focus on whether the supply of the token, its type and current holders.