The asker is wondering what will happen if their Facebook account gets hacked, and how to prevent it from happening.
Keep a secure password, include numbers, letters, characters and so on. Have good malware protection on your computer. Don’t access your account on public computers that might be infected with malware. If you do find out you have malware, change the password (from a different computer) and clean the infected machine. These actions substantially decrease the possibility of your account being hacked.
If you do get hacked the main risks are spreading malware to your friends, getting locked out of your account and embarrassment. If you use your account to manage business pages the ramifications could be more serious.