My friend imposed restrictions on me in my house so I am going to hide his laptop.
That might not go well. Why did you hide it in your room?
Because - I have many important important things to do with it.
It can be annoying to be controlled in your own house but you shouldn't hide your friends things from them. It is wrong and it might be against the law.
In this case you don't have to worry about it since I have my data on that laptop I can tell them that is mine.
But your friend might have a record of paying for the laptop and could show them that it is his. Just talk to him about why you are upset and stop hiding his things before you get in trouble.