That is a very ambiguos statement in not specifying which MiniTool program you are running, MiniTool Partition Wizard???? MiniTool Power data Recovery??????
Please note that a 1TB HDD will read as 931GB. Are you assuming a 1TB HDD as 3TB HDD?
If you are running MiniTool Partition Wizard 12 and in that Partition Recovery Wizard, at the end of the scan you will get a screen showing partitions found. Double click on those and check whether you can see the folders and files. Post the screenshot. Note: Even if it finds some relevant partitions, you will not be able to write it. You will need to get a licence for it. So just
post a screenshot and close Partition Wizard.
Open Partition Wizard again, and
post a screenshot of how your drives look in it. - The very first screen that appears when you launch PW 12.
Post a screenshot of Windows Disk Management. Disk Management - Post a Screen Capture Image - Windows 7 Help Forums ( Make sure you hide the Console Tree as well as the Action pane and adjust the seperators in the disk list so that all data is visible as indicated in this guidelines.)
These screenshots will let us know whether it is a 1TB drive or 3 TB drive.
When you have done this, please
disconnect all secondary drives in the dektop.
Boot your PC. Does it boot?
If it does not boot, it would mean that the boot records most probably written into that 3Tb drive and it is then a job for Windows 10 experts here, to undo that and make Windows bootable with the primary disk. May be it will be prudent to reinstall Windows 10 afresh after disconnecting all the drives
Either way, once you are up and running, we shall deal with the corrupted 3 TB drive and check whether there is a possibility of recovering any data on it. ( as per your statement you have also written some data into it . If so that could have overwritten some of the original data.)
I won't do anything till it is confirmed that you can run Windows 10 from the primary disk alone and not in conjunction with that 3Tb drive.