Maximum supply is the total number of coins/tokens that are restricted from being created on a blockchain protocol, including coins that are already or will be in circulation in the future.
Max supply is the maximum limit of total tokens that can be produced on a blockchain network. This amount is determined by the contract code that governs the tokens and is usually specified in the whitepaper when the crypto project is first launched.
Max supply consists of tokens that are already in circulation, still locked, not yet minted at all, and in the future. The amount cannot be changed once the token contract is active on a particular blockchain such as Ethereum, BSC, Solana, etc.