You are looking for an exchange platform where your users can come and trade with your erc20 token against bitcoin, ETH, ltc etc..
I have made similar project where admin can able to add erc20 token in exchange platform and users can trade for that. I have created BTC,LTC, ETH, XRP, bitcoin crash and many more wallets
We can talk more over chat, I will share my project link. Have made two exchanges