Yes people would assume you have curl. Curl is often used to install programs. And curl is definitely one of the things that can do malicius things this way. So you are right to be hesitant to use commands that you don’t understand. Most Linux users have forgotten how hard it is to learn the first stuff with no preaquired knowledge.

If you have googled “what is curl and how is it used” you may have found some relevant info.

I have given up on Linux because installing was hard in the past

There are some tools that make installing software easier. Like “appimage” files that are single files that (after you make executable) are completely self contained.

Flatpacks and snaps have an “store” like experience.

.deb files are also sometimes simple (also need to be made executable) (depends on the distro)

Unfortunately there is no .exe file experience.