how can I disable tap to click on the elementary os? I've tried disabling it from the "Mouse & Touchpad" menu on Settings but it doesn't work.
If you have a Synaptics touchpad (which I believe is on most laptops), you can use synclient to modify these settings.
To install simply run
sudo apt install xserver-xorg-input-synaptics.
In this case
should do the trick.
You can put this in your
~/.bashrc to make it permanent.
Refer to the man page for more options.