Ask HN: Whats something you wish you knew when you started managing people

I'm in a position where I've got to be managing people in my company. Not a strength of mine, especially the project management piece. Where I'm more of a founding engineer that knows the niche industry product _too_ well, so we can't hire around it, only train around it. While we are expanding, I'm the head of impossible amounts of projects. I'm in a constant make the best, worst choice to keep things moving situation. Everyone exec level knows all of this and is being very gracious as I learn on the fly. Still, I really want to improve but struggling as it feels like I never have time to even do project/people management the 'right way'.

If there are books, courses, or anything that had a big impact on your management skills, I would love to hear your story!