how can I code a dll injector very simple

okay I want to try to make something like this.


Okay the background is like the cmd just plain black and it injects all the dll's in the folder/place it's at, and it just asks you what .exe you want to inject to. Then you just start the program/exe and it will inject it and say injection complete or injection failed.


So very simple and hope that the coding is very simple I'm asking all your readers because I tried to search this up on google and youtube and nothing like this well like what I want so... how do I make it?