You can most definitely write a story and ask for ideas at the same time, that doesn’t determine an author.
As for ideas, you’ve given kind of a broad spectrum. Since you’ve mentioned something about wanting a male mc, why don’t you look at your favorite books/shows and pick apart different things that you like about it to then create into your own story?
If you want a specific idea then how about a setting in NY (or some other big city) where your mc (boy or girl) finds out that he has an innate ability while going through their daily mundane routine. (And build off from there?)