There is no one answer @jmjmjm0123 as there are several methods, processes and products you can use depending on your environment. The best thing I can tell you is the key to successfully restoring any website (regardless of the reason) is preparation, preparation and preparation.
While I have my favorite tools I won't push you to any but instead check out How To Do A Quick And Easy Complete WordPress Backup and PREPARING FOR THE WORST Disaster recovery for WordPress sites for some great information. I hope that helps?
roy darling *my posts seem a lot shorter in my head