Hi there,wondering what's the best system to use to get Internet connection, just been to a festival with zero connection for 4 days ,what set up is best ,thanks

Mobile phone hotspot, if you have a data package as part of your contract, is the simplest option.

Buy yourself a Mobile Router with an external Antenna. That will pickup a 5g signal of up to 2 miles away.

Always a good one D-Link F518 Portable WiFi 6 5G NR/4G LTE Cat 12 Router w/ Embedded SIM Slot (1.7Gbps AX)

Last time I went to a festival-in-a-field, the local mobile network had signal but was completely saturated because it wasn't designed for XX thousand people showing up at this rural location. That's a different use case from regular camping where there's few other people about.

Might be worth looking at Starlink. They keep changing the prices and terms but I think on some of the packages you can switch it on and off - ie don't pay the monthly fee when you don't need it.

I was at a festival recently with the same issue. Rural location, good signal strength, but mostly no chance of any data transfer and calls wouldn't connect. We managed ok without, but the only solution that would have worked there would have to have been satellite based as the local cell towers were no doubt completely overwhelmed by thousands of users all trying to get connected at the same time. No mobile based dongle would have been of use there.

oh do what I do, get a drive bang vids etc on it then plugin to my tablet via usb c and watch them.