Notebook no longer boots up, how can data be obtained?

Are there any products that can help me? Could probably send it to an expert and he'll screw the whole thing on for me but would rather do it himself.

Simply take out the hard drive and install it in a PC.

There's no other possibility?

If the laptop no longer outputs an image. Then you need another PC / laptop.

But that is also described very vaguely.

What does "won't boot up" mean?

You could install Linux on a stick using another PC and have the PC boot from the stick. Then you could see whether the files can still be saved. There are many tutorials on how to do this. Here is one:

https://praxistipps.chip.de/...ikel...%20

What exactly does "won't boot up?"
It does not begin? No picture? Broken?

With a PC, the data can be easily accessed by removing the hard drive
or read them out via e.g. A live operating system (if the laptop hardware is OK)