Simply put, a token represents what a person owns, while a coin denotes what they're capable to own. Additionally, everyone has used a token at least once in their life even if not in this form. For example, your car title is a token.
Tokens can eventually become coins when the project develops its own blockchain and migrate their tokens to the new blockchain as a coin. Successful migration cases include Binance Coin (BNB), Tron (TRX), Zilliqa (ZIL) which previously existed as tokens on the Ethereum blockchain.