I’ve been doing two different “courses.”
To start I highly recommend the 7th Edition of Big Nerd Ranch’s iOS Programming.
It’s pretty easy to follow along, and benefits from years of teaching this material at their in-person boot camps.
If you’re up for a bit more of a challenge, Stanford’s CS193 is updated every year. The current course is free here: https://cs193p.sites.stanford.edu/
It’s important to get up-to-date material, because Swift and the Apple frameworks are a moving target. Both these sources are from this Spring and include SwiftUI.
Both assume some previous programming experience.