How to boot from second NVMe M.2 SSd?

[Jonifyy]

I recently bought a second NVMe M.2 SSD (2tb) for my Omen 16 Laptop. It's already in the second slot of my Laptop and I also cloned all the data from the original ssd (500gb) on it (macrium reflect). Now I want to boot from the 2tb ssd but it doesnt show up in the boot manager. So how do I boot from it? It should have windows on it because I cloned it from the 500gb ssd wich has windows 11. I did some research and some people say i have to disconnect the original ssd and then it will automaticly boot from the new one. Can I just do that or is there any possibility that my Laptop will be damaged after that? Or should I switch the ssd slots of the ssds?

I have no problem with setting my Laptop up new if it doesnt work but I prefer to just clone all data. Thanks for your anwsers. 

[WAWood]

You said you did a cloning using Macrium Reflect.  I use that all the time, so I need to know if you used the option to clone the disk (all the partitions) or if you only cloned the OS partition.  If you did the latter, the SSD is missign an ESP partition -- which it need to have for booting.

[Jonifyy]

I cloned the whole disk.

[WAWood]

OK, then it SHOULD have worked -- as I have done this numerous times with Macrium Reflect.

If you made Rescue Disk (USB) with Macrium, then boot from it and choose the option to repair the boot records.  That should fix any boot problem.

[Jonifyy]

So what should I do now? The question is how can I boot from the 2tb ssd. What has a rescue disk to do with that?

[WAWood]

The rescue disk reinstalls the boot loader files -- so if you point it to the second disk, not only will it rewrite the files, it will also select that as the default boot drive.  So after that, you should be able to boot from it.