It depends on which coin you have. But you can try Dexes based on ethereum. Also you can check your token on listing website like coinmarketcap or coingecko. If you see your erc20 listed on any good centralised exchange you can go with that too. But if you are don't know all about these things then you could watg these things first and then go for sell or something.
It's always better to give some time rather than lose your portfolio for not having proper knowledge. That's it.