As someone who isn't scared of the terminal, I don't get the fear really. What's the difference from opening a store app or web browser and searching for an application and asking your package manager to search for an application? Either way, you just type the name and it gives you results. I guess the package manager you at least know it's from a mostly trusted source (usually, unless you do something to allow exceptions), while a web search isn't always.

Why you find terminal instructions online is because it works for every system though. It doesn't matter what distro you have, or what packages; they all have a terminal and the same base. This isn't true for package manager instructions though, because there are several, and different distros provide different ones.