Store the SOFTWARE completely on the second VOLUME of the HARD DISK - But how?

I have a tricky problem for the smart minds among you.
It's basically about partitioning hard drives. I use Windows 10.
I would be happy if you could take a moment and read my question.

Actual goal:
I partitioned my hard drive and created a second volume. The original volume should be for work, the second new volume for hobby.

Problem:
Software that I only want to save in the volume hobby is not completely installed under the specified file path despite changing the installation path, but some folders are still in the folder system of the main volume (work volume).
Example 1: I installed Minecraft (no comment.) In the volume hobby. The game launcher is now there. As before, the actual folders are in the working volume below:
Work (C. \ Users \ (*****) \ AppData \ Roaming \ .minecraft
Example 2: I installed the FL Studio music software in the Hobby volume. However, a folder with graphic icons for all plugins has been installed in the "Documents" folder, which is stored in the working volume.

Consequence of the problem:
Accordingly, there's no point in separating work and hobby. On the contrary: I feel that I only create additional chaos, because I have software that is partly installed on a volume A, partly on a volume B. And the two volumes are physically independent of each other. What happens on volume A has no effect on volume B - as I see it, it creates a certain instability within the software.

Own supposition of the cause of the problem:
I suspect this is sometimes because the second volume for hobby does not have the prepared folder structure (library, program (x86), etc.), as is the case with the main volume. Accordingly, I do not suspect that the software knows where to install various folders in the "empty" volume and automatically saves it under the predicted file path of the main volume.
I also suspect that the main volume has the first status and that all software is programmed to integrate into this primary volume, which is peppered with commands - that's my theory.

I hope I have not confused too much, I hope the experts among you can tell me…

A) … Why the software folders are not installed under the file path changed in the installation process, but in the standard location.

B) … How I can create two "equivalent" volumes (same folder structure and what else is behind it) - In the distant sense like two user accounts within the same account.

C) … (if I'm wrong with my assumptions) how I should best proceed otherwise to strictly separate over two volumes of work from hobby.

I would be very happy about your help!

I'll keep it short.

Various programs must have a structure in C.

Furthermore, it is often imperative that Windows needs this structure.

And often setups do not allow anything else.

First of all thanks for the quick answer!
I was almost afraid of that.
Do you see a problem in the fact that the programs are now partly stored on one volume, partly on the other, as I fear?

The only problem is…

If you reinstall Windows you also have to reinstall the necessary programs because the references are no longer available under Windows.

All right, I assume it would be best to unpartition the hard drive and save everything in the original volume C.

Why do you want to deal with partitioning data carriers if in this case this makes no sense at all? If anything, a second disk would be interesting. If one partitioned disk blesses the time, both partitions are gone at the same time. There are no performance advantages, not even with SSDs.

The only reason for partitions is to be able to start multiple operating systems.

What you plan to do will not work that way, see also the answer from WillEsWissen64.

What comes close to this would be a second Windows installation on the second volume, but I can't say for sure whether it works at all. I once had a similar installation (Windows 10 on one disk, Windows 10 upgraded from Windows 7 on another disk. However, these were two physical disks, not partitions on the same hard disk.)

By the way, it's not a bad idea to set up multiple partitions, one (usually the first) for the operating system and programs, and one (or two) for data. Has the advantage that these partition (s) can be retained if a new installation is necessary. The fact that you should make a backup of important data (on another, external data carrier) is actually a matter of course.

The only reason for partitions is to be able to start multiple operating systems.

There are other reasons, for example to keep the data on a separate partition, which could be retained if the operating system is reinstalled.

Maybe it was a bit blue-eyed, didn't even have on the screen that Windows 10 would not be active on the second partition, but that explains a lot.

Thanks, I think I finally understood the difficulty behind it, Windows is no longer active on the second partition if I understand it correctly.
I think I undo the partitioning and leave everything on the C partition. That would be the most sensible, right?
Oh yeah and as far as the last point with the backup is concerned, I thought if one partition smeared, the other is gone. How then can the second partition act as a backup?

I agree.

It also makes little sense to restructure the data by separating the partition.

It only makes sense if you actually have 2 or more hardware disks.

But this has more to do with data security.

In my case I have 2 external (both NAS) disks to back up my data.

Many thanks for the help!

There are no other reasons unless you still live in the 1990s. Huge memories are available today for a few euro like a 128 GB USB stick, which should be enough to save current data. It's no longer about 128 MB.

A USB stick as permanent storage for important data? Yeah, right!

You misunderstood something or read it incorrectly, for backup I had written that it should be done on a different (external) data medium.

And as far as partitions are concerned: if one can no longer be accessed, it does not mean that you can no longer access the other, this would only be the case if the hard disk itself had (physical) damage or the controller would be defective.