Laptop hit the floor. It's difficult if not already impossible to connect to WiFi. Sometimes laptop can detect WiFi, particularly the one at home, but the signal is usually weak. Sometimes it shows option of connecting but whenever I try to connect, it either says it's connected though I can't connect or it stops detecting WiFi. What are my options please? Is there some way to externalise the WiFi detection? Like I plug in something that detects WiFi?
I'll structure this response by increasing complexity of the solution.
Turn it off turn it back on. Use the power button to shut it down, some systems use quick-boot if you shut down from within the operating system. Quick-boot preserves the system state and as such cannot act as a system reset.
(This one costs money)Buy an external WiFi adapter or NIC, as mentioned in the previous response. Also as mentioned previously, make sure your laptop has at minimum a USB 3.0 port if you want any reasonable speed.
Reinstall the drivers. This requires a small amount of technical knowledge, and can bork you WiFi card if done improperly. Using system info, identify your WiFi card. Then download the latest drivers from the website if you have windows, or your operating system's requisite driver repository for all other os's. Uninstall the current driver, even if it's the same version as the one you acquired. Reinstall the freshly downloaded driver.
Replace the WiFi card.(This one costs money) Don't do this if you have no knowledge of computer internals. Identify the make and model of your WiFi card. Purchase an identical one or a compatible replacement. Download the drivers for your new card. Uninstall your old drivers. Replace the WiFi card. Install the new drivers.
If none of these work, consider repositioning yourself closer to the router, or replacing you router with one that produces a stronger signal. Worst case scenario you might have to replace your laptop. Edited to give structure, posting the response initially smushed all the points together.
You have some options here.
Most Laptops come with a very basic card provided, 90% of the time, by Aetheros. They often either do not connect to an antenna or they are connected to thin wires that loop the monitor and serve as an antenna.
The component connection is relatively universal, so if you can get your case apart, you can upgrade this card yourself. It's a small card about the size of one of those grocery store discount card keychain fobs.
Alternatively, you can plug in an external USB NIC. These work better than most internal cards, as they have their own affixed antenna. The only downside is that if you only have older USB ports and not the 3.x variety, your connection speed will be limited to about 10MBs/80Mbps in most situations. These are often sale items on Amazon.
If your laptop is old enough to have a PC-Card slot, there are also wireless options there, but if the computer is that old, you're probably better off in the market for a new machine.