"The point of passive income is that it makes you what you want with little to no work. So for example a SaaS product that doesn't require too much maintenance (a couple hours per week) netting you a few thousand $ per month."
So the point is to get something for nothing? Money without work? Everybody wants that.
So what SaaS product requires little maintenance but nets a few thousand dollars a month? Maybe something like that exists. But creating it would have required considerable investment of time or money, which eliminates the "little to no work" part.
Likewise for selling some physical product. Tons of people are doing this on Amazon. It's not taking them much work. It's also not making them much money.
I think the OP's question just doesn't make much sense. The only reason someone asks about "passive income" is because they want money without working for it. I can think of only two ways to do that. One is to inherit it. One has no control over that. The other is to build up political influence so one can seek rents (in the economic sense.) Even this method requires some work because it requires investment in capital or influence (neither of which is easy.)
Some investors are said to get "passive income" but that's because they got some money in the first place. Plus, they use resources to get more resources. Buffett's income really can't be said to be "passive" when he spends time and talent doing research and analysis.
Yeah one can get "passive income" by putting money in a bank or in stocks or something. Good luck getting decent returns with that...which is why investors are seeking out higher rates of return...which takes work...which, guess what, is not "passive".
In short, "passive income" does not really exist. Unless someone is going to give OP money through inheritance or dumb luck or Powerball, she's going to have to get out and work for it like everyone else.