First steps: Start Julia in a certain folder in VSCode

Hi,

my Path is for example this folder saved somewhere

From the question:

All I wanted is to run a Julia file, thats it. The example I tried is the link (PowerModels, but any would work for me, I just need an example), it does have a Project and Manifest file. I am in the right path, I guess, and I did activate and instantiated (what I think is the current folder with those files).

So to back up to the absolut beginning in VS Code: “File” → “Open Folder” and my Terminal Commant line shows PS D:\Daten\Julia\PowerModels.jl-master>
(… the cd(“D:\Daten\Julia\PowerModels.jl-master”) command then does nothing, right? But I should be in the working directory) I can change the environment in the left corner of VSCode and chose “C:\users\myName.julia\environments\v1.7”, but that doesnt help … and typing in “using Pkg” doesnt work in any case.
Runing one line of Code by Ctrl+enter in a file in that folder starts Julia and I can type in using Pkg and then activate and so on…

That cant be the way, right?
But that is also another problem due to inexperience, I hope.

I just want to run the Code, shown in the read me:

Basic Usage

Once PowerModels is installed, Ipopt is installed, and a network data file (e.g. “nesta_case3_lmbd.m”) has been acquired, an AC Optimal Power Flow can be executed with,

using PowerModels
using Ipopt
run_ac_opf(“nesta_case3_lmbd.m”, IpoptSolver())