Do actually exist a website, page (even a section in Bscscan, Etherscan) where I can track the supply of a certain token and figure out how it changed during the existence of the token?
I mean like the "historical data" section in Coinmarketcap.
First of all you need to know the platform of the token which one you need to know about circulating supply or max supply. After that you can search via bscscan/ethscan/tronscan. And you can easily see the token details. Also if the token listed on coingecko/coinmarketcap/poocoin or etc coin price and volume tracking site then you can easily get the token details. You can easily find the max supply and circulating supply. Max supply is fixed. But circulating supply can be changed.