HaloMods "Classic" Read-only Archive

i need help i don't know whaat im doing i download

CE
HEK
Gmax(can't get registration code)
HEX Workshop

what else is there and what do i do none of the other tutorials help

i've never modded in my life so if you could help i would be greatful!!

What is HEK? CE lets u play custom maps and blah blah blah...

But what does HEK do? Do they cost anything to download?

Do i need to pay for anything at all? or is it all free?(Hopefullly...)