Can people on windows 10 and playstation 3 play minecraft together?

No. PS3, 3DS, and Wii U's version of the game weren't updated with the latest updates.

PS4 has the latest update but doesn't allow cross-play because Sony has their collective heads up their rears.

Windows 10 (not the java version), Switch, XBO, and Mobile versions can cross-play with each other.

No.

No.