I want to invest in a coin that is stable.
No such thing! The best thing to do is diversify. Don't buy just one coin. Buy a small amount of 5-10 different tokens.
Just some friendly advice
Sounds like excellent advice to me.
True. You shouldn't put all your money in any single coin or product. You must need to diversify your funds to reduce future risks. You should select a coin based on the use of their coins because there are many coins not useful. I have invested some money in these coins IOTA, NEM, Waves, LTC, Ripple, Burst, ETH and NVO.