It is practically impossible for anyone to start any form of investment be it bitcoin investment or any form of investment without a source of income.infact not just source of income the person should have a good cash flow inorder to be able to sustain the investment since they are venturing into gambling with bitcoin which doesn't require long term goals
How are you going to even buy bitcoin when you don’t have a source of income, where will the money which you will be using to buy the bitcoin come from? I don’t even think that’s possible, and Incase maybe you are gifted a money, and you decide to invest it in bitcoin, if you are in need of money, you are still going to sell back the bitcoin, so it’s just better you don’t even invest the money at all.
If you are planning to invest in bitcoin, then make sure you have a source of income, you have a emergency funds, so that whenever their is any problem, then you will be using the emergency funds to take care of it, you won’t be touching your bitcoin investment, but if you don’t have any emergency funds, whenever their is problem, you will end up selling back your bitcoin, which might even be at loss.