My dad has an old Samsung laptop and it blows all the time, especially when you surf the internet for a long time. My father suggested unscrewing the back and cleaning everything, but my sister doesn't trust that she doesn't want what is broken afterwards. What do you mean by reason?
I would not tinker with any laptop myself.
Ask an expert if he'll clean the laptop.
There are tutorials for almost everything on the Internet. Just take a look how your laptop is doing. Then you can decide whether you trust yourself to do it or not. In general, it's actually not rocket science, but with some devices it can be quite cumbersome.
Unscrewing and cleaning the fan usually helps.
Some, especially older, laptops have bolted openings specially designed for maintenance, while others are a little more complex to disassemble.
I would look up the best way to open the laptop on YouTube, then you can clean it yourself.
I find it unnecessary to go to a "professional" for cleaning, because it takes less effort and effort if you just do it yourself.
I assume that the fans or coolers are a bit dusty, should be easy to fix with a cotton swab.