I suppose you are running our official Node-RED Image. In this case, there is the underlying software Evok that makes the PLC I/Os (including 1-Wire) available to the Node-RED IDE via Unipi nodes. To avoid 1-Wire bus access conflicts, the appropriate kernel module (named ds2482), managing also sysfs access through /sys/bus/w1/devices, is disabled by default.
Basically, you have two options (that cannot be combined mutually):Use Evok and Unipi node(s) to read data from sensors in Node-RED - then follow this tutorial. This is the default state. Disable 1-Wire support in Evok (comment the OWBUS section in /etc/evok.conf), enable the module loading( add/uncomment "dtoverlay=ds2482" in /boot/config.txt), and use some other nodes (e.g. the one meant in your post) to access the 1-Wire bus.