You can get started with PureScript 0.12.0 easily by using this repo.
If you have everything installed, you should be able to follow this:
> psc-package install
Installing 3 packages...
...
Install complete
> pulp run
* Building project in /home/justin/Code/purescript-0.12.0-hello-world
...
* Build successful.
look, show on Record:
{ apple: "banana" }
Please see the installation page in https://purescript-resources.readthedocs.io/en/latest/installation.html
No, unless you know exactly what you might use Bower for, you do not need it at all. You should be using Psc-Package like this repo does.