I plan to change the hard drive in my laptop. Is it possible to get all data including Windows on the new hard drive without needing a new product key?
Not that it works. So you can make a backup of the hard disk and play on the new one "on it". But believe with the windows you will have problems
It depends, newer notebooks have already stored the keys on the mainboard. Otherwise just clone the plate should be enough. There's enough software for this
No matter what you do, do a backup
This is called cloning, there are various software for it and also pure hardware solutions for copying hard drives…
Yes, I would advise against cloning. Buy a hard drive case for 5 euro. There you install the old hard drive. You build the new one in the laptop, install Windows and so on and then you connect the old one to the laptop. Now you can move the data you need from the old to the new one. Read out the product key before reinstalling. Then nothing can go wrong, but if you have Win10, you don't have to enter it if everything runs smoothly. He remembers it that way.
When you're done transferring data from old to new. Can you format and test old ones. If it is still good, you can use it as a backup hard drive.