The beach at the park is really nice and it's a great place to go swimming. One of the best things about it is the lighthouse, which has amazing views. There's also a nature hike that takes about an hour, and there are ropes to help you climb up or down depending on which way you're going. I suggest starting the hike by the campgrounds instead of the parking lot because it's an easier route. Make sure to bring water because it's not a trail you want to do without it, and definitely don't wear flip-flops! We saw some monkeys with their babies near the campground by the bridge, but we didn't see any wildlife on the trail.
The entrance fee to the park is 200 baht per person, and it's about 40 baht for a motorbike. There's a restaurant, changing rooms, and showers on site, although they're not very clean.
Our favorite part was the quiet beach area, which had beautiful sand and clear, warm water. If you want some shade, you can find it under the bushes along the edges of the beach.
Overall, it was a nice day trip to the southern part of the island!