Airdrops do not take up a lot of time so you can easily do them along side a full time job. Also they do not give out many tokens so it will be very difficult to make enough profit to make this your full time occupation.
If you really want to make the most out of the airdrops, spend some time looking at the projects and then only participate in good projects. Also be careful with what information they are asking from you. Airdrops should not be asking for many personal details. If they do, you should be sceptical of whether they are a scam.