It’s likely that SATA controller mode is not set correctly and that’s why your SSD is not recognized by BIOS. So you can configure the SATA controller settings in BIOS.
Since the steps to configure BIOS are different due to the brands, so here we take Lenovo laptops as an example.
Restart your computer, and press the F2 key after the first screen.
Press the Enter key to enter Config.
Select Serial ATA and press Enter.
Then you’ll see SATA Controller Mode Option. Choose the IDE Compatibility Mode.
Save your changes and restart your computer to enter BIOS.
Besides, if you have reinstall Windows 10 on your new SSD, I suggest delete the OS file on old disk. You could also use GUI interface bcd tool such as EasyBCD to modify BCD information on another disk.
Similar case.
https://neosmart.net/forums/threads/bcd-on-another-disk.17387/
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