Combining two hdd partitions WITHOUT data loss is real?

Question

Hard disks

Win 10. As usual - one section for the system, the other for junk. You need to save the section with junk.
There is a utility:
Control Panel -> System and Security -> Administrative Tools -> Computer Management -> Disk Management
In it, I simply delete the system partition and increase the partition with junk.
Actually the question is: will the data from the second partition remain untouched when the partition is expanded? Scary.

Answer 1

We have repeatedly encountered situations of data loss when manipulating disk partitions.
It is clear that in many cases, clients may not say anything or not fully understand what they were doing, but in general I would advise you to back up first, then do something.
You can incl. create a disk image in order to roll it back in case something happens and have everything, including the system, in the "exactly as it is now" state.

Answer 2

The drive on which the extra space is being added is not removed. Even the disk from which you need to take some space. Data is deleted only if you clicked delete or format.
For a guarantee, you can create a small disk, throw data there and build it up.

Answer 3

Merging or merging partitions used to be a popular feature in all disk/partition and file system management programs. One of the disks remains (main, boot, or any other), the second "merges" into it, becoming a folder on it. This is of course, if it was necessary to transfer along with the data.
If you can delete everything from the "second" (in your case, the first) disk, then there are no problems at all - you delete the partition (that is, there will be unallocated space), choose for the rest - "expand" - this is done literally ten seconds - a minute, two.
But with the "back" extension, I don't remember if there are any peculiarities, it seems it shouldn't, but all of a sudden ... Check it on a virtual disk - create a VHD and practice on it - check it out.

Answer 4

If the size of the trash is not larger than the volume of the system partition, then after cleaning the system disk, you can transfer the junk there (as I understand it, it is the first on the hard disk). Then remove the second disk and expand the first.
Well, if possible, backups are also needed.
If there is external storage, then you can simply transfer the junk to it and work quietly with the disk.