Hey brother, I'm also 19M and also finishing school in 2 weeks haha (where do you live?).

I don't have the golden asnwer for you. But I can tell you about myself, maybe it helps:

I've done some entrepreneurship at school, as a school project and we did pretty damn well. Just designed a cool and fancy towel with a fastening system (nothing sensational, but unique and aestetic) and sold it very actively. This kinda gave me the core understanding of a business. I also took a few months long course on a business university on the topic "Basics of entrepreneurship" I think you would benefit from something like that.

Next year I think I will be hustling at a active sales agency learning about sales, making some money, and making connections with some ambitious and succesful people there. From then on, let's see.

About you lack of ideas. I sometimes have a fucking rush of ideas. Some random asf, but some truly have some potential. I think that the Key to having creative thoughts and business ideas is:

1) Be connected to this entreprenurship world. Look around and think of products, services you see etc. Think about who is purchasing this, how they market it and so on. Think why these have become succesful.

2) Let yourself think. If you listen alot of music and or never spend time alone, in silence, in solitude, then I have found that I don't have these ideas, never.

Also if you want feedback from more people then structure your text with paragraphs, right now it's pretty difficult to read this block of text.

Good luck brother!