Exe To Shellcode _top_ — Convert

Compile and run. If your EXE was a message box, you should see the popup.

Further reading (tools to search)

The final output is a blob of raw bytes that, when executed in any process, will unpack and run your full EXE. convert exe to shellcode

...you are likely looking at reflective PE injection. Compile and run

Writing this loader from scratch is tedious. Fortunately, the security community has developed tools to automate this process. when executed in any process