Have from my laptop, which is equipped with 128GB SSD and 1TB HDD.
I replaced the HDD with Samsung evo 850.
But now it's like I want to run everything about the evo because of the speed, how do I do it best?
How can I additionally install Windows on the evo, since Windows runs on the other ssd?
I would recommend you the following:
Clone the contents of the HDD (at least the relevant one) to the SSD. Then in the UEFI / BIOS select the partition of the SSD for the boot. But please select the fragmentation for the SSD.
Then, if everything works, you can use the HDD as a backup or storage and format it beforehand. Instructions and videos can be found on the net.
Why should Windows run from one SSD to another?
Just disconnect the system from the programs / data.
how that works is e.g. Here:
https://www.pcwelt.de/...66508.html
By the way, my C is not half full with SSD 120GB for some time!
Additionally
Simply choose the EVO as installation path, Windows can manage multi-boot very well.
After installation is then asked at each startup whether you
Windows 10x64
or
Windows 10x64
want to boot.