Flash Voyager (if this is the one) is a usb stick with up to 64Gb of storage, for the big one.
It's not really a backup program; more a medium for storing files etc.
The medium you use for a full backup depends on how full your disk is; that is, how many Gb of information need to be backed up.
Several backup programs exist. These can make images of your entire OS, and using them is somewhat like using system restore.
They include the popular Acronis, Norton GoBack, and
Macrium Reflect (free version available.)
The program needs to be installed. Once installed, you will need an external medium large enough to store the backup on. Typically this would be an external hard drive. A 64G flash drive would be sufficient for some systems.
Then the help files should be consulted, and the program set to make the backup, how you want, and where you want.
On my computer making a full disk image in this fashion, on to a 500G hard drive, takes about 30 minutes.
(Haven't had to test the restore function so far.)