Good day!

I am not a programmer normally, for me its not a problem to create some function that will for example encrypt, but then I really don't know that I should use cmd to apply it to a file and after which I get an encrypted file. Or when I create a function to separate the web address from the rest of the link, how do I apply this to the browser, how do I connect it and make it work? Can someone give me some basic explanation of it?