Laptops have become thinner, lighter, faster and their screens brighter than ever. But with all this technology packed into a smaller format, it can be difficult to repair them when the time comes. However, many laptop problems can be solved easily and cheaply with common tools, spare parts and a bit of effort. Some repairs are no more difficult than high school art projects.
That said, there are modern laptops that are very hard to open and repair. If you don't see any screws, you're in for a challenge. For example, Microsoft improved the repairability of the Surface Laptop 3 between versions without changing the core design. Manufacturers often use tricks to make repair difficult, such as using patented screws, refusing to publish repair documentation, or gluing parts together.
If you decide that a laptop can't be repaired, there may still be a chance to reuse some of the components. However, this could cause the laptop to overheat, the fan to run continuously and loudly, and may even cause the laptop to crash.