For long-term investments, you need to choose cryptocurrencies that are in the rating at least in the top 30. They are more stable, traded on many exchanges, and the probability of a sudden scam is minimal. For analysis, it is best to use Coinmarketcap - there is a rating of all cryptocurrencies by capitalization, you can see a lot of useful information. If you are interested in information on a particular coin, you can enter it in the search and analyze it