My uni's only got a few in person events this year, and I know it's the same at other unis, with some only having online events. Chances are you'll be fine spending the whole of freshers in self isolation.
Where are you coming from? It might be worth checking whether you definitely have to quarantine when you arrive, as some countries don't. The list changes all the time, so you could also check nearer the time, as it may have changed.