• A coin is a digital currency similar to the physical currency.
How is an intangible digital currency or a cryptocurrency similar to a tangible physical currency like a dollar bill?
However there are cases that a token can become coin like eos and tron network that resides on erc20.
Tron the coin doesn't use the Ethereum blockchain. It has its own network. You are probably thinking of USDT, a token (even though it's called a stable
coin) that can be transferred over the Tron blockchain. While writing this post I just remembered that Tron used to be an ERC-20 token, but sometimes in 2018/2019 it migrated to its own network, so maybe you were talking about that. Such migrations happen often once the projects develop their mainnets.