I just want to know, if some measures to keep my Mac safe, which should be turned on, are turned off by a third person.
Who is this third person?
If you allowed someone else to use your Mac, presumably it is someone you trust and not a "hacker" or someone intent on doing something nefarious. That someone should also be using his or her own User Account.
As g_wolfman wrote nothing is going to determine if your Mac has been "hacked" or not. Don't even bother looking for something to do that. If you find some utility, app, etc claiming that ability, it's a scam.
If you have reason to believe your Mac is not functioning correctly then by all means please write back and explain the circumstances.