Welcome to the forum!
I’m not talking down to you, but you really should read the following…
Neither KDE Plasma nor GNOME are operating systems. They are desktop environments — and very different ones at that — while the underlying operating system is the same between all official Manjaro editions. Considering that graphics drivers are handled by the operating system, the installation should have proceeded with equal chances of success between the two versions you’ve tried.
The most logical explanation for what you’ve observed is that the download of the Manjaro Plasma ISO had become corrupted somehow, and/or that you did not correctly flash it to a USB stick (or burned it to an optical disk).
It is therefore imperative that you always verify the checksum of the downloaded ISO against the one listed under the eponymous button for the pertinent ISO on the download page. The checksums must be an absolute match — a single differing character already points at corruption.
As for creating a bootable USB stick, everyone here — myself included — recommends Ventoy. It is available for GNU/Linux, Microsoft Windows, and yet other operating systems, and it is easy to use.
Simply format the USB stick with Ventoy, and then you can simply drag & drop ISO files into the pertinent folder on the stick — as many ISOs as the stick can hold — and then you simply reboot off of the stick, and it’ll present you with a menu with all the ISOs it contains. Select an ISO, then select “Boot in normal mode”, and off you go.