Yes, you should test for Covid before going to a gathering

“If you are vaccinated and boosted and are not at high risk, you may choose to test yourself and attend the event, and then test again three to five days following the event. You may also decide that you want to mask while attending the event even if your host is not requiring masking,” says David Souleles, the director of the Covid-19 response team at the University of California Irvine. “If you are someone who is at higher risk for serious disease, or live with or are frequently around someone who is at higher risk, you might decide to pass on a particular event in order to reduce your risk.”