In short, You can (Up to date systems) mount it in 1 go with something like
mount -o loop /path/to/my-iso-image.iso /mnt/iso
Step 1, what is the next loop number we can mount on ?
This will probably result in something like /dev/loop0 (Which is the next ready loop to map the ISO to
losetup /dev/loop0 /path/file.iso
Then, mount the loop device with the mount command
mount /dev/loop0 /mnt/dir
That’s it, The new solution and the old, As always, i keep things here as a not to self, because sometimes I come across older computers, and I forget how it was done since all the mounting I do now the new way