BTC, ETH, NEO, BNB are generally Most Favorite. But otherwise there is nothing really stable as such in the crypto world. Do your own research before investing and aim to invest into something which is going to be around in the long run. Read the whitepapers, get to know the founders and scan the internet for every single detail you can. Best of Luck!
It is true that in the world of cryptocurrency everything is very volatile and it is certainly quite difficult to predict the price.
and when it comes to favorite altcoins, of course, ethereum is still at the top,
besides that, of course there are still altcoins that have great potential such as polkadot, BNB and many more