I often participated in airdrops and never received coins that could be sold and made good profits. I think this type of earnings is not suitable in order to receive money for investment thanks to it. It is much better to find a job in an offline business and allocate part of the money to invest in cryptocurrencies.
Airdrops are not the right choice and you can come up with your own services and make money out of those. Then you can invest that money in bitcoin or altcoin of your choice, but best is to go with the king of crypto currencies. Airdrops, bounty programs and ICOs were good few years ago but these do not produce same results anymore. Having a job has its own importance. It will just increase your number of income sources.