Should i manually backup my wordpress before upgrading?

You need to backup both your Web site’s FILES and the WordPress DATABASE. FileZilla can only “see” files.

I’ve never used HostGator, but I see that they have cPanel. Unless HostGator stripped out the feature, cPanel has several ways to do backups. It is probably easiest to backup the WordPress database as one operation, and then backup the root directory of your domain name as a second operation.

Alternatively, you can use FileZilla to backup the root directory and use one of the WordPress backup plugins to backup the WordPress database.

You can backup in your hostgator cpanel look for icon Backup

There is no need of this
but you can backup your files
PS: Backup your files daily

I would do both just in case your hosting does not backup everything. You never know.

Boston WP is right. Hosts make mistakes. But an even more common problem is that a host’s Support folks get “backed up” with problems and don’t get to your recovery request fast enough and the backup you want to restore from has been deleted automatically as part of their backup cycle.

Equally common is a incorrect restore by a host’s Support staff that wipes out something else on your site.