I’ve fished on the jetty before and caught sheepshead and redfish but that was closer to spring. If you fish on the cut side of the jetty you will need a heavy weight. Use shrimp or cut bait
The beach gets really crowded with swimmers, surfers, and such at St. Andrews. The jetty or the pier are your best/safest options at the park. The pier is shorter than the ones in town so not sure if they catch kings there or not. I like to fish the jetties with light tackle and allow the bait to drift. Enough weight to get it down but not so much you get into the rocks. You tend to get hung up a lot either way. I have caught bull reds freelining frozen cigar minnows. Sheepshead and mangroves on shrimp. Live is better but frozen works too. People catch Spanish on gotchas. A lot of fish go through that pass. Keep your bait and any food close as the raccoons that live in the rocks will steal it. They can open coolers and will even take bottled water. If you have kids and just want action try the pier/dock by the boat ramp. Typically not crowded but mainly pinfish as it is pretty shallow but no rocks to stay hung up in.