Hello. My name is***** to JustAnswer. I'm reviewing your question now, and will post back with your reply momentarily.
First, you will need to be with your router and a computer.
What is the exact make and model of your gateway and do you have just the gateway
or do you have another router you bought yourself hooked up as well. Most comcast equip
is gateways which has a modem/router in one. The extra router is sometimes added by individuals.
Use this guide below starting on page 29 of the document (not number 29 in your finder)
It will show you how to use your computer and log into your router. Once you log in,
you will follow the steps to change passwords (and much more) from there in the menu. If you need help
with this, let me know.
If you are satisfied with the help I have provided, please remember to click and submit a 5 star rating on this page. Your feedback is important as it is the only way I am credited for assisting you. Thank you.~Franklin