Lets say i have 5 ETH at myEtherWallet and there is a ETH hard fork. What would i need to do, to get the new coin?
As said there are multiple "things" called forks, in many cases those are actually airdrops where you have to do certain actions, like having the coins on certain exchange, or prove something in certain website; I will not care about those, although you seem to think about them as hard forks.
If a proper hard fork happens (like it was for BTC/BCH), from what I know, all you need is to have the coins in a wallet
where you own the private keys. Some exchanges may be kind and give you those coins, some are not, and some may change their policy. But if you own the private keys, those will work on both blockchains after the fork too, hence you'll have the original coins and the forked ones too.