HaloMods "Classic" Read-only Archive

i downloaded it, but how do i put it in?

Hi everyone. I am new to modding and there are several questions i would like to ask. 1. which program do i use to mod? 2. is there a step by step guide on how to mod? 3. is modding cheating? cause i used a premade mod and everyone got mad at me... thanks in advance for answering. i hope to contribu...