If you want to backup a website hosted at HostGator, for example, to upload it to your hosting account at Hostinger, follow these steps:
Log in to your HostGator's cPanel
Click on the Backups menu in the Files section
Under the Full Backup section, select Generate/ Download a Full Website Backup
Select the Home Directory option from the Backup Destination drop-down menu
Specify your Email Address if you want to get a notification when the backup is complete
Click on Generate Backup, which will create the backup file in tar.gz format in your home directory
Now you can then download the backup via cPanel, FTP or SSH
Additional Resources
You can check the guide from HostGator here: How to Generate & Download a Website Backup
If you need further help, make sure to contact HostGator support