> If I open it, I am afraid I won't be able to put it back together.
That happens, but: the thing was broken anyway, and, now it's twice broken and disassembled, so you can throw it away in good conscience, hopefully having figured out how to approach it correctly the next time, so it's not even a waste of time.
This. A long time ago I remember making a custom screwdriver head to open a video game cartridge by softening a bic pen cap over a candle, then pressing it over the cap for 10 seconds. Let it cool, and voila.
I've also found the same approach indispensable for doing simple carpentry without all the specialized tools of a wood shop.
If you look at some of the breakdowns on ifixit, there might be an area where they needed 4 screws. In another laptop, they would have been identical screws, but in the Apple they are all different sizes. Each one is specific to the area it's holding so they could cram in more components. It may not be as easily repairable but it is good engineering.