I am a gamer and the latency is killing my game.what can I do about the latency

Hardwire it

Change companies. Xfinity isn't a gamer friendly company.

There a few things you can do, 1st swap out the modem. Modems should be swapped every year. That should fix it. 2nd if it doesn't fix it then increase your megabytes. Also connect directly to your modem using a ethernet cable. That should do it.