You can change your mouse's DPI in the Settings menu on your computer, or if you have the right kind of mouse, by pressing the DPI button on it.
You can try to boost your cellular signal with simple fixes like moving outdoors and keeping your battery from entering low power mode.
People often complain about slow internet speeds from their home Wi-Fi routers. Especially those with Wi-Fi with antennas are often confused about which direction to point the Wi-Fi router's antennas.