Hi Dennis,
I am Dave, I will help you with this.
Yes, that is PowerShell and that is a legitimate process.
1
Is PowerShell popping up when you start your PC?
If so, please provide a screenshot of that full screen, so I can try to work out what is causing that.
2
Open Task Manager (Ctrl + Shift + Esc)
Select the Startup tab of Task Manager
Please provide a screenshot of that Startup tab.