WiFi Connection Problems With Dell Inspiron 7559

Hi, I have a Dell Inspiron 7559 and I seem to have some sort of WiFi problem with it. Basically, my computer won’t connect to certain WiFi networks, or will do so but very weakly. My mobile phone recognizes our home WiFi network as full bar and other networks around us (about 9), and so does my friend’s laptop which is in the same room as mine, except my friend’s laptop recognizes the WiFi as full bar as well as the other networks while mine only recognizes 2 and very weakly.

I’ve tried downloading the drivers, troubleshooting, uninstalling the WiFi in Device Manager and reinstalling, putting battery on maximum performance and so on, and nothing seems to work.

Thanks in advance.