I still prefer *bin over Lemmy for the UI and the domain-blocking feature, even with Lemmy having post-hiding features. 🙂
Dunno what sort of setup you have, but what I would do, considering my setup and by being a tad on the neurotic side, is to unscrew and detatch any drives but the one to be flashed. This, I think, is the only way to be absolutely sure nothing goes in the wrong place.
If you mean different physical drives, I would suggest detatching the drive with the already installed system when installing the second one.
Also, Linux installers may behave differently from one another, so I would suggest testing on another machine if possible, or at least backing up what you cannot afford to lose in the current machine, shrinking the Windows partition with its native partition manager instead, and picking a system whose installer can spot the correct partitions, maybe e.g. Mint with its option to be installed alongside an already installed system, or Endeavour which, from what I remember, can detect empty partitions.
Also if during install, grub is not set up to have both Linux and Windows as start options, there is a grub manager on Linux too, so that can be salvaged.
And lastly, a word of warning, and reiterating a past point, testing something as big as a dual boot in a computer with sensitive and already existing data is playing with fire.
Tried flashing an USB stick and putting the system ISOs in the stick afterwards?
On not finding anything, see if OpenSuse has anything like apt-cache. On Debian-based systems, it helps a bunch, as it looks for packages (programs) containing in the name or description the keyword you are looking for. Regarding messing the installation, making back ups periodically and keeping the more volatile stuff you do not want to lose on different physical drives could help.
Been some years since I last used Fedora, so not able to confirm nor deny anything. Sorry for not being able to help further. =/