A true newbie trying to do a UDEV command, need help

Here is my problem, UDEV rules. I know nothing about how to to them, or how to get to them. So, how to I navigate and browse to the path, as this help desk person tells me? Is it with a terminal window? This problem is referencing in getting a bitcoin wallet to work. Below is what instructions I was given. I do not know how ot get to the paths as instructed. Please help.
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Hello there,

Sorry for the confusion. Basically you will need to browse to this path: /etc/udev/rules.d/51-usb-keepkey.rules and edit the "51-usb-keepkey.rules" and add the rules written below:

# KeepKey: Your Private Bitcoin Vault
# http://www.keepkey.com/
# Put this file into /usr/lib/udev/rules.d or /etc/udev/rules.d
# KeepKey HID Firmware/Bootloader
SUBSYSTEM=="usb", ATTR{idVendor}=="2b24", ATTR{idProduct}=="0001", MODE="0666", GROUP="plugdev", TAG+="uaccess", TAG+="udev-acl", SYMLINK+="keepkey%n"
KERNEL=="hidraw*", ATTRS{idVendor}=="2b24", ATTRS{idProduct}=="0001", MODE="0666", GROUP="plugdev", TAG+="uaccess", TAG+="udev-acl"
# KeepKey WebUSB Firmware/Bootloader
SUBSYSTEM=="usb", ATTR{idVendor}=="2b24", ATTR{idProduct}=="0002", MODE="0666", GROUP="plugdev", TAG+="uaccess", TAG+="udev-acl", SYMLINK+="keepkey%n"
KERNEL=="hidraw*", ATTRS{idVendor}=="2b24", ATTRS{idProduct}=="0002", MODE="0666", GROUP="plugdev", TAG+="uaccess", TAG+="udev-acl"