Please help with shellcode example

I want to satisfy my curiosity (ALL DONE FOR EDUCATIONAL PURPOSES).
The shellcodes topic seemed very interesting and the first thing I tried to do was to output a MessageBox, I succeeded, but now I want to understand and debug it in more detail.
My goal is to display in the dialog box the name and number of the process from where my shellcode was executed, to see if I am running it correctly.
I am developing this on MASM32. Thanks for your help in advance :pray: