Can I watch Bluray movies on a Windows 10 laptop?
If your drive can read Blu-Rays: yes.
If you have a BlueRay drive… YES
And how do I know that
If there's a drive installed that "can" Blueray and a corresponding software player is installed, nothing should stand in the way…
Yes. If the computer has a Blu-Ray drive and software to play it.
If you have a BluRay drive in your laptop and the corresponding playback software, of course
By checking the specifications of your drive.
The easiest:
Put a Blu-Ray disc in the drive and see what happens.
That should be on it (not only the CompactDisc logo but also the Blu-ray logo).