To be specific…

Install something from the main repo:

$ paru -S package

Install something from the AUR:

$ paru -S package

To search for a package, in the main repo or the AUR:

$ paru -Ss search-term

With the search results, it clearly labels if something is from the AUR or extras or the main repo, and you can make it show AUR results first or last in the config.

https://github.com/Morganamilo/paru

I don’t actually use pacman directly at all, I use paru for everything and it’s seamless.