Yes you are right, if for example you do not have any income at all the first thing you should think about is not investing, but finding a job first so that you have income. Because if you do not have income how will you have discretionary funds. Even if you do not have a job how will you buy necessities for your life. That is why if you want to invest in bitcoin, but do not have a job, the solution is definitely to find a job first so that you have income. Because basically investing in bitcoin requires discretionary funds, whether it is large or small. Because if you force yourself to invest in bitcoin like using borrowed money, I think that is a bad idea. So my advice is to hone your skills first, then after that apply for a job and if accepted then you can think about investing in bitcoin after all your needs are met.
I think it would have been better to use the word "source of income" instead of using the word "job" here. Whether we work or do business or earn in any other way is not important for investment. Rather, you need to have a source of income for investment and have discretionary funds after meeting the necessary needs.I think he is using the word "Job" for a person who do not have funds or a source of income. So those people can only job or provide any service to raise their income. Such people can't initially do business as it also requires money.
By the way, you need to have the motivation that you will save every penny and invest in Bitcoin BTC. For example, you may decide to skip a pizza party and put that money in bitcoin. However, it seems that these small investments aren't profitable but collectively, one can accumulate bitcoins over a period of time.