It is very important to have backups of your site and database. The majority of hostings offer backup service; however, if you don't have it we recommend you to read the following information: https://codex.wordpress.org/WordPress_Backups
You may also set your own backup with the help of plugins from WP catalog. We recommend using UpdraftPlus WordPress Backup Plugin for the creation of backups and automation of the whole process.
Taking into account a wide variety of combination of hosting configurations, Web-server software, and installed third-party plugins, no one can guarantee 100% compatibility and absence of conflict of every configuration. Therefore, we recommend you to make a backup of your site and database before any updates of WordPress or Crane theme.