I am new to erc20 tokens, so I was wondering if I could have some help. I'm considering starting an erc20 token and I have one main question. When someone buys my erc20 token, does the Ethereum they bought it with goes directly to me, or does it go somewhere else. Also, when someone exchanges the token and exchanges it back to Ethereum, will I have to pay anything, or does exchanging only lower the price of the erc20 token. Thank you to anyone who helps out.
The ERC20 is simply a token standard. It says what functionality the token contract should have. That functionality enables basically to have a ledger of owners and to transfer ownership of X amount of tokens.
The standard doesn't say anything about trading or prices. Those are done with different means - for example trading is often done though a (de)centralized exchange. The mechanisms how trading work depend on the exchange. Also the different fees depend on the exchange.