Currently, if you want to buy any altcoin, it is very difficult. You can't choose an option quite easily. Also, the crypto market is currently volatile. In such circumstances if one wants to buy altcoin. So what should be the main focus?
There are already a lot of suggestions from other members here in the forum but here's my own method on how I verify tokens personally before investing in that token.
Probably the first thing that I check is coinmarketcap and search the token in if it is available on that website, if it's not available probably its too early to invest in that token, if its available check the market where that token is available if it is already listed is many exchanges or something if it doesn't list in probably around 5 exchange it's probably too early to buy the token.
Then check the token website, check the utility, is it a Defi token or something, check the website if it's legit, check the whitepaper. If everything checkout you could probably decide if your gonna buy it or not. I mean investing always has its risk.