I am doing some research and it seems like there is no maximum supply. Am i right? With the coins created with PoS, inflation will just go on indefinitely?
Yes, but that's not necessarily a bad thing. I'm sure I read a great article about it a few months ago but I'm not sure where (and don't think I bookmarked it).
The real issue is if the inflation/growth is too high (as is the case with a few cryptos - there are a few at 100% or more), new coins will devalue the existing coins and only encourages people to hoard coins. If your not staking them your coins will effectively decrease in value.
With EverGreenCoin the rate of growth is relatively low (currently maximum of 7% but as already mentioned it's going to be lower overall). At a rate like that the value of each individual coin shouldn't be affected by new coins being created because the new coins created a day is relatively low.