Understanding on Boot USB for Windows Deployment

Hello
I have inherited my environment and am trying to understand what the previous tech did to set up our windows deployment the way he did.

I have a winpe boot usb.
When I boot to it, runs a file called startnet.ps1 (powershell). I am then prompted for my admin credentials.
It then prompts me for an image on our network (WIM file). I can browse the the wim files from anywhere and I can select Win 7, 8.1, 10 (Enterprise licenses).
It asks what disk I want to install on.
It asks me for a drivers folder to install drivers for that specific model of computer or laptop (on the network).
It asks if it is an unattended install or not
It finally asks to confirm.

It then begins to install the OS, drivers etc and prompts for nothing.

I have looked at the boot USB, but cannot find anywhere where it is saying to go to a specific place on our network; or even the name of the network.

But it all works flawlessly.

Can anyone suggest as to how this was done? I'd like to learn to duplicate this going forward.

Thank You

Terry

Welcome to the forum it should all be in the PowerShell file

Thank You for the reply.
But how does the usb get pointed to the powershell script on the network?

Thank You

without seing it and from what you say if it runs startnet.ps1 it should all be in there post a copy if its not to big is this on a domain or workgroup