[C# or C++] Load DLL with manual mapping. x86 + SOURCE

I need to load a dll with manual mapping. The injection method must be done with "manual mapping", so if you do not understand this please do not respond to this project. This is a fairly simple small project. It just needs to be a simple console application that allows me to input a process name to target, and input a path to dll that will be injected into the target. This must come with the source as well, preferable C#, but i will also take C++. Thank you.