Some questions about making your hack UD

There are 4 questions, i'm new in coding, so please help.
I want to know how to make junk codes, and where i need to put it in my hack.
What's polyloader doing at all?
Is enigma protector will helps you making your hack more undetectable?
Do i need junk codes, or my hack will be undetected without it?

If you wrote your cheat yourself, it'll be undetected by default.
You wont need junk code. VM Protect/Enigma protector can't hurt, so you might as well use them.
Junk code might look something like this,

string whaterve = "asdasdasd";
whaterve += "jdakjsdkajsd";

I reccomend putting it in methods that are never actually called. They will be included during compilation if you "use" the variable in some way (2nd line of my example) but as I said, not necessary to even add it.