Well I'll try my best to answer all of your questions here goes:
Depends on what kind of hack your using, if we're talking about a bypass you just need the bypass, you don't need cheat engine or pro dayz.
There are some non battleye servers, they are just hard to find.
You can find some bypasses in the market place or from some of the users here, and you will need to look for some users that have some vouches and ones that you can trust.
Bypasses usually stay good for until battleye or if dayz updates, I'm not sure about day z updates.
And yeah you will get banned if it doesn't work, or if you find someone that has a good reputation you will most likely get one that works.
Press the thanks button if you don't mind, answered a lot for you