like majority says it is Ethereum or Defi based coins because those are on the pick days now.
Ethereum
Ripple
Polkadot
Chainlink
if you are willing to invest and risk then better take a look at these 4 so you may find the best contender for investing and holding.
why don't you enter USDT? whereas USDT is a nice coin even very stable. The price change is only slightly, different from other altcoins that can downfall deeply.