1. Bitcoin
Yep, that's it. Bitcoin is all that matters. Investing in 99.9% of cryptocurrencies, especially in the long term, is worse than investing in penny stocks.
Indeed bitcoin is a reliable crypto to invest for short or long term. Its proven to be profitable and less risky compared to altcoins.
However its good having alts too in our crypto portfolio, I have eth, bnb and iost.
You can whatever coins you like as long as you did your research because you'll invest your hard earned money thus its better to be cautious.