I am new, and this is probably a trivial question, but I have not found an answer anywhere. It looks like I cannot create native apps with Unity, and if people want to run my apps they need to install the unity player on their devices. correct? thanks.
Nope! You can create standalone players for both Windows and MacOS, which will run on any supported hardware without the need to install any separate players. The only place where you need to install something separate from your application is in the web-player- Unity needs a special plugin to be able to run inside of a browser. As for mobile devices, I’m probably not the one to ask since I have next to no experience with them, but as far as I can tell once you have created your deployment build you can install and run it on whatever device you want to- be it iOS or Android (depending on your build target)- without having to install anything else first.