If the product isn't there yet, don't market it. Spend more time on it and make it better. Make it so someone is willing to pay you thousands of euros for the value of your thing.
I really love how Ali Abdaal charges one thousand dollars for his YouTube course and a lot of people are taking it. To me it is a deep lesson in how to make money as a marketer. If your product is solid enough, people will pay you 1000 dollars for it, because they'll end up winning from the deal. If there is a deal where you're the winner, you have to take that deal. Of course. It's almost like you don't even have a chance to say no, why would you, if you'll end up winning.
If you want to make money in paid advertising such as YouTube ads and Facebook ads and stuff, I really don't see a way out of doing it like Ali Abdaal is doing and making a product that is worth a ton and many people are willing to pay you that amount. Otherwise you could lose thousands of euros in your marketing.
So if you want to make money as a marketer, it's good to do your research and see it like this - if you want to make money and end up with a net profit, you need to have a really solid product to begin with that people are willing to subscribe to or pay you a bunch of money for it. Otherwise you just might end up losing your money doing marketing. Of course if you don't care about losing your money, then go ahead. But otherwise, it's good to consider, have you mastered your product development yet and created something that truly is worth a thousand dollars or even more?
Best, Aapo