You'll know you've installed git right if you can run: `git --version` and you get an output like `git version x.x.x`
You'll know you've installed nodejs right if you can run: `node --version` and you get an ouput like: `vx.x.x`
You'll know you've installed npm right if you can run: `npm --version` and you get an output like: `x.x.x`
Here is a simple way to install brownie.
pip install eth-brownie
Or, if that doesn't work, via pipx:
pip install --user pipx pipx ensurepath
restart your terminal, then
pipx install eth-brownie
You'll know you've installed brownie right if you can run: `brownie --version` and you get an output like: `Brownie v1.18.2 - Python development framework for Ethereum`