First off, how do you even find out about these coins?
Do you mean those coins you mention? Hm, I do not find out about that. You can check on CMC to find the info but you should visit their website to see more details.
Second, what exchanges can you even find these coins? It seems almost all these altcoins are related to ETH. Does it involved pancakeswap/metamask and things like that? Is it easy to learn?
In CMC, you can find many things, including the exchanges for the coins. If the coin is not listed on CMC, you need to wait for some time or ask their team what exchange they used.
Third, these coins don't have any correlation to btc? [/b]
I guess it is not but I do not know. But many altcoins follow where bitcoin moves as bitcoin lead them.