If I use the makecode editor to create the code, it generates:
pins.touch_set_mode(TouchTarget.P0, TouchTargetMode.CAPACITIVE)
However, if I try and run this, it can't find 'pins'.
Note: I then investigated further and found out how to do this before submitting my question...
Capacitive mode can be set for each pin, e.g.
The last line checks whether the pin is touched - usually in a loop.
Hope this saves other people some time...