In order to attempt a restore, you need to go to the "Terminal" and make the Library folder visible.
In the "Summary" tab you will be able to see all the necessary details about your i Phone.
In this way, some settings will also be backed up and restored to your i Phone later.
If this is not what you want, you can choose to backup and restore i Phone without updating to your computer selectively according to your need by using i Skysoft Toolbox - i OS Data Backup & Restore or the common method. This is the easiest way to restore i Phone without updating. Choose "Data Backup & Restore" Menu i Skysoft Toolbox - i OS Data Backup & Restore has versions for both Windows PC and Mac.
After the process is completed the whole operation is finished.
As you can see, restoring your phone without updating is not that hard to do, and even if you might encounter some errors from time to time while performing that process it shouldn't trouble you that much, because, in the end, you are going to have a successfully restored phone and that is the most important thing.