Brett needs to connect his laptop to his phone and use it as a hotspot. Leo says that the iPhone does have a hotspot mode, but some carriers will want to charge him for the privilege. He can enable it in the phone's cellular settings. Then he can connect his laptop to his phone via Wi-Fi. This will be impacting his data plan though, so he should keep that in mind. But if his connection keeps dropping, that sounds like an issue with the laptop.
Another option is to buy a USB Wi-Fi access device, or even a MiFi card. That will give him a separate connection that he can connect up to five devices to. It's possible that due to the age of the laptop, it may not support his phone.