Of course you can earn good money from Ethereum. If you invest in Ethereum, you don't need to acquire much knowledge, because you will only invest and hold, and I don't think you need full knowledge for this holding. But still if you acquire knowledge, there is no harm in it but you will gain more. This is a good time to invest in ethereum, because right now the price of eth is very low, you just need to invest and hold for a long time. Right now Ethium is worth 2.5k maybe it will be worth over 5k in 2025 when Bitcoin crosses 100k. So if you start investing now and hold for long time then surely you can earn good amount of money.