Truffle not installing on Mac - Big Issue

I uninstalled and reinstalled Truffle.

npm install -g truffle

Then I navigate to a folder I created on my desktop and enter:

npx truffle

That shows a loading bar in the terminal and appears to be setting up something in the folder

When finished it says Truffle v5.4.11 - a development framework for Ethereum and lists commands below. (build, compile, run, etc.)

I then open the folder I did npx truffle in and nothing is there. in my terminal i do:

truffle init

it says “-bash: truffle: command not found”

not sure how to get around this problem. This is a relatively small community so it’s been hard to get support.

My mac is version 10.13.6 macOS High Sierra Macbook Pro (Retina, 15-inch, Mid 2015)

Would love to use the program. Does anyone know why it’s not working?