Javascript won't help too much for this but its good to know 2 languages. There are some open source/sample botnets written in python you can check out with a quick search.
The thing that is really going to trip you up is networking. Your C2 (Command & Control) needs to stay up and hopefully not be easily traceable to you. You also want to have backups/fail safes so if your domain or C2 get taken down you can collect your bots again.
Don't forget you still have to get the client installed on some systems which is its own challenge.
Ok, what network adapter do you have though? You need to look it up, zsecurity I think has a list of all the common ones and a few really cheap external ones for under $20 with shipping