Not only 3 ways, but there's more, such as offering your service just like logo designing, writing white paper, or to be a part of the team as blockchain developer if you have that skill. And for me Airdrop nowadays is just a waste of time.
that's right there's a lot of better ways on how to earn in crypto not just these 3 ways, try to review this thread if you're willing to learn those ways. i don't think that these ways of making money in cryptocurrency is suitable for everyone, for example the first one is mining, it seems like not everyone can afford to buy mining rig because the electronic parts are very expensive and you have to calculate the electricity you've to consume for your power supply and if you're suggesting also the cloud mining, i don't it is very applicable. yes you can actually earn, but it also takes a lot of your time.