Edit your /boot/config.text & append the line below to the end of the file. After, reboot the Raspberry Pi
dtoverlay=w1-gpio
Setting a custom pin can be configured as well by specifying the gpiopin
dtoverlay=w1-gpio,gpiopin=17
17 above would be BCM 17 (pin 17) on the gpio header
The device connected to the gpio pin would be listed under /sys/bus/w1/devices
ls -l /sys/bus/w1/devices