If you're trying to 'burn' the Zorin OS .ISO file to a USB stick, you have some options:
if you have Windows, you can use the free CD Burner XP Pro to 'burn' the .ISO file to the USB stick.
If you already have a bootable version of Linux, you can go into the Disks application, select the USB stick, select the '3 vertical dots' button at upper-right, select "Restore Disk Image", select the Zorin OS .ISO file, then set it to burning.
You can 'burn' Ventoy to the USB, then just drop the Zorin OS .ISO file onto the larger of the two partitions on the USB stick (it'll be the big, empty partition)... you don't have to extract the Zorin OS .ISO file or change it in any way, just drop it onto that partition. You might also download the Win10 PE .ISO file, so you can boot Windows or Zorin OS. I use Windows to update the machine's firmware (since the files only come in Windows-specific formats).