Lubuntu 20.04: Can see but not connect to wifi (I can connect at friends house though)

Solution 1:

What happens if you reset the router and use the original password? And then try to log in with that password.

The reset that I talk about is more brutal than reboot. It is resetting from all the settings, that you (or other family members) have done - back to factory settings, which means that for example the passphrase for wifi is back to what should be printed on a sticker on the router (maybe on the bottom). You may need a pin, and use it to press a microswitch in a small hole. See the manual of the router, should be available via the internet, if you have no paper copy.

Solution 2:

To eliminate any other issues, try changing your wifi password to something with just alpha-numeric characters - no special characters.