Those who said those words to you that cryptocurrency investment is low risk and high return doesn't really know crypto that much. We are all well aware that investment in crypto goes as the higher the risk, the higher the plausible return. If you want to earn big in here, you should have the guts to invest a lot of money. On the other hand, committing such acts requires strategic and wise planning so that you wouldn't end up losing a lot of money. You have all the freedom to invest as much as you can but it would be more advisable that you only invest the money you can afford to lose.