The ONT is a small box that's mounted to the inside of your home. It's what connects the outside fibre optic cable to your router.
It's important to think about where this ONT should be located before the technician arrives. You'll want the ONT to be where you use the internet the most, and in a central location where the WiFi signal will reach all of your devices. You wouldn't want your router to be located in the garage right? So the ONT shouldn't be installed there.
If you have a larger house, you may want to consider a whole-home WiFi system. After all, one router can only provide WiFi so far.
Get in touch and have a chat about the best location to place the ONT. This has huge impact on your Fibre experience - so you'll want to get this right. First time.